As filed with the U.S. Securities and Exchange Commission on May 10, 2022

Registration No. 333-263467

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

AMENDMENT NO. 3

TO

FORM S-4

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

Frontier Group Holdings, Inc.

(Exact Name of Registrant as Specified in Its Charter)

4545 Airport Way

Denver, CO 80239

Telephone: (720) 374-4550

(Address, including Zip Code, and Phone Number, Including Area Code, of Registrant’s Principal Executive Offices)

Barry L. Biffle

President and Chief Executive Officer

Frontier Group Holdings, Inc.

4545 Airport Way

Denver, CO 80239

(720) 374-4550

(Name, Address, including Zip Code, and Telephone Number, including Area Code, of Agent for Service)

With copies to:

Approximate date of commencement of proposed sale of the securities to the public: As soon as practicable after this registration statement is declared effective.

If the securities being registered on this form are being offered in connection with the formation of a holding company and there is compliance with General Instruction G, please check the following box.  ☐

If this form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  ☐

If this form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act.  ☐

If applicable, place an X in the box to designate the appropriate rule provision relied upon in conducting this transaction:

Exchange Act Rule 13e-4(i) (Cross-Border Issuer Tender Offer)  ☐

Exchange Act Rule 14d-1(d) (Cross-Border Third-Party Tender Offer)  ☐

The Registrant hereby amends this Registration Statement on such date or dates as may be necessary to delay its effective date until the Registrant shall file a further amendment which specifically states that this Registration Statement shall thereafter become effective in accordance with section 8(a) of the Securities Act of 1933, as amended, or until the Registration Statement shall become effective on such date as the Commission, acting pursuant to said Section 8(a), may determine.

The information in the accompanying information statement and proxy statement/prospectus is not complete and may be changed. These securities may not be issued until the registration statement filed with the U.S. Securities and Exchange Commission is effective. The accompanying information statement and proxy statement/prospectus is not an offer to sell these securities and does not constitute the solicitation of offers to buy these securities in any jurisdiction where the offer or sale is not permitted.

PRELIMINARY—SUBJECT TO COMPLETION, DATED MAY 10, 2022

MERGER PROPOSED—YOUR VOTE IS VERY IMPORTANT

To the Stockholders of Frontier Group Holdings, Inc. and the Stockholders of Spirit Airlines, Inc.:

On February 5, 2022, Frontier Group Holdings, Inc. (which we refer to as “Frontier”) and Spirit Airlines, Inc. (which we refer to as “Spirit”) entered into an Agreement and Plan of Merger (which we refer to as the “merger agreement”) that provides for the combination of the two companies. Under the merger agreement, Top Gun Acquisition Corp., a wholly owned subsidiary of Frontier, will merge with and into Spirit, with Spirit continuing as the surviving corporation, in a transaction we refer to as the merger.

Pursuant to the terms and subject to the conditions set forth in the merger agreement, at the effective time of the merger, each outstanding share of Spirit common stock, par value $0.0001 per share, (which we refer to as the “Spirit common stock”) (except for treasury stock or shares owned by Frontier) will be converted into the right to receive $2.13 in cash, without interest (which we refer to as the “per share cash consideration”), and 1.9126 shares (which we refer to as the “per share stock consideration” and, together with the per share cash consideration, the “merger consideration”) of voting common stock, par value $0.001 per share, of Frontier (which we refer to as the “Frontier common stock”).

Although the number of shares of Frontier common stock that each Spirit stockholder will receive is fixed, the market value of the merger consideration will fluctuate with the market price of Frontier common stock and will not be known at the time Spirit stockholders vote on the merger. Based on the closing price per share of Frontier common stock on The Nasdaq Global Select Market (which we refer to as the NASDAQ) on February 4, 2022, the last trading day before public announcement of the merger, the per share stock consideration represented approximately $23.70, for a total merger consideration of $25.83 in value for each share of Spirit common stock. Based on the closing price per share of Frontier common stock on May 9, 2022, the latest practicable trading day before the date of the enclosed information statement and proxy statement/prospectus, the per share stock consideration represented approximately $16.70, for a total merger consideration of $18.83 in value for each share of Spirit common stock. We urge you to obtain current market quotations for shares of Frontier common stock (currently traded on The Nasdaq Global Select Market under the trading symbol “ULCC”) and shares of Spirit common stock (currently traded on the New York Stock Exchange under the trading symbol “SAVE”).

Based on the fully diluted number of shares of Frontier common stock and Spirit common stock as of February 4, 2022, the last trading day before public announcement of the merger, it is expected that Frontier stockholders will hold approximately 51.5%, and Spirit stockholders will hold approximately 48.5%, of the fully diluted shares of the combined company immediately after the merger.

Spirit will hold a special meeting of its stockholders (which we refer to as the “Spirit stockholders”) virtually, via live webcast on the Internet at www.virtualshareholdermeeting.com/SAVE2022SM on June 10, 2022 at 9:00 a.m., Eastern Time (which we refer to as the “Spirit special meeting”). At the Spirit special meeting, the Spirit stockholders will be asked (i) to consider and vote on a proposal to adopt the merger agreement (which we refer to as the “merger proposal”), (ii) to consider and vote on a non-binding advisory proposal to approve the compensation that may be paid or become payable to the named executive officers of Spirit that is based on or otherwise relates to the merger (which we refer to as the “compensation proposal”) and (iii) to consider and vote on a proposal to approve the adjournment of the Spirit special meeting, if necessary or appropriate, including adjournment to permit further solicitation of proxies in favor of the merger proposal (which we refer to as the “adjournment proposal”). The board of directors of Spirit (which we refer to as the “Spirit board of directors”) has unanimously (i) determined that the merger agreement and the transactions contemplated thereby, including the merger, are in the best interests of Spirit and its stockholders, (ii) declared that the merger agreement, the merger and the other transactions contemplated thereby are advisable and (iii) approved the execution, delivery and performance by Spirit of the merger agreement and the transactions

contemplated thereby, including the merger. The Spirit board of directors unanimously recommends that the Spirit stockholders vote “FOR” the merger proposal, “FOR” the compensation proposal and “FOR” the adjournment proposal, if necessary or appropriate, including to solicit additional votes for approval of the merger proposal.

The board of directors of Frontier (which we refer to as the “Frontier board of directors”) has unanimously (i) determined that the merger agreement and the transactions contemplated thereby, including the merger, are in the best interests of Frontier and its stockholders (which we refer to as the “Frontier stockholders”) and declared that the merger agreement is advisable, and (ii) approved the execution, delivery and performance by Frontier of the merger agreement and the transactions contemplated thereby, including the merger. Concurrently with the execution of the merger agreement, Indigo Frontier Holdings Company, LLC, the holder of 178,834,034 shares of Frontier common stock, or approximately 82.4% of the shares of Frontier common stock outstanding and entitled to vote on such matters as of February 4, 2022, executed a written consent in lieu of a meeting (which we refer to as the “Frontier written consent”) approving the issuance of shares of Frontier common stock in connection with the merger as contemplated by the merger agreement (which we refer to as the “Frontier stock issuance”). As a result, no further action by any Frontier stockholder is required in connection with the approval by Frontier stockholders of the Frontier stock issuance, which is the only Frontier stockholder approval required in connection with the merger.

The attached information statement and proxy statement/prospectus describes the special meeting of Spirit, the merger, the documents related to the merger, and other related matters. Please carefully read the entire information statement and proxy statement/prospectus, including the “Risk Factors,” beginning on page 24, for a discussion of the risks relating to the proposed merger. You also can obtain information about Frontier and Spirit from documents that each has filed with the Securities and Exchange Commission.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of the securities to be issued in the merger or passed upon the adequacy or accuracy of this information statement and proxy statement/prospectus. Any representation to the contrary is a criminal offense.

The date of this information statement and proxy statement/prospectus is                 , 2022, and it is first being mailed or otherwise delivered to the Frontier stockholders and the Spirit stockholders on or about                 , 2022.

NOTICE OF STOCKHOLDER ACTION BY WRITTEN CONSENT TO FRONTIER STOCKHOLDERS—WE ARE NOT ASKING YOU FOR A PROXY AND YOU ARE REQUESTED NOT TO SEND US A PROXY

To the Stockholders of Frontier Group Holdings, Inc.:

The board of directors (which we refer to as the “Frontier board of directors”) of Frontier Group Holdings, Inc. (which we refer to as “Frontier”) approved an Agreement and Plan of Merger dated as of February 5, 2022 (which we refer to as the “merger agreement”) pursuant to which Top Gun Acquisition Corp., a wholly owned subsidiary of Frontier, will merge with and into Spirit, with Spirit continuing as the surviving corporation, in a transaction we refer to as the merger.

Pursuant to the terms and subject to the conditions set forth in the merger agreement, at the effective time of the merger, each outstanding share of Spirit common stock, par value $0.0001 per share (which we refer to as the “Spirit common stock”) (except for treasury stock or shares owned by Frontier), will be converted into the right to receive $2.13 in cash, without interest (which we refer to as the “per share cash consideration”), and 1.9126 shares (which we refer to as the “per share stock consideration” and, together with the per share cash consideration, the “merger consideration”) of voting common stock, par value $0.001 per share, of Frontier (which we refer to as the “Frontier common stock”).

The Frontier board of directors has unanimously (i) determined that the merger agreement and the transactions contemplated thereby, including the merger, are in the best interests of Frontier and the stockholders of Frontier (which we refer to as the “Frontier stockholders”) and declared that the merger agreement is advisable, and (ii) approved the execution, delivery and performance by Frontier of the merger agreement and the transactions contemplated thereby, including the merger. Immediately following the execution of the merger agreement, Indigo Frontier Holdings Company, LLC, the holder of 178,834,034 shares of Frontier common stock, or approximately 82.4% of the shares of Frontier common stock outstanding and entitled to vote on such matters as of February 5, 2022, executed a written consent in lieu of a meeting (which we refer to as the “Frontier written consent”) approving the issuance of shares of Frontier common stock in connection with the merger as contemplated by the merger agreement (which we refer to as the “Frontier stock issuance”). As a result, no further action by any Frontier stockholder is required in connection with the approval by Frontier stockholders of the Frontier stock issuance, which is the only Frontier stockholder approval required in connection with the merger.

Frontier has not solicited and will not be soliciting its stockholders’ authorization or approval of the merger agreement, the merger and the other transactions contemplated by the merger agreement, including the Frontier stock issuance. Frontier is furnishing this Notice of Stockholder Action by Written Consent and this information statement and proxy statement/prospectus to provide its stockholders with material information concerning the actions taken in connection with the Frontier written consent in accordance with the requirements of the Securities Exchange Act of 1934, as amended, and the regulations promulgated thereunder, including Regulation 14C. Further, this Notice of Stockholder Action by Written Consent and this information statement and proxy statement/prospectus shall constitute notice, pursuant to Section 228(e) of the General Corporation Law of the State of Delaware to Frontier’s stockholders who have not consented in writing to the actions set forth in the Frontier written consent and who, if the actions had been taken at a meeting, would have been entitled to notice of the meeting if the record date for notice of such meeting had been February 5, 2022, the date the Frontier written consent was delivered to Frontier.

The enclosed information statement and proxy statement/prospectus provides a detailed description of the merger, the documents related to the merger, and other related matters. We urge you to read the information statement and proxy statement/prospectus, including any documents incorporated in the information statement and proxy statement/prospectus by reference, and its annexes carefully and in their entirety.

BY ORDER OF THE BOARD OF DIRECTORS
		Howard Diamond Secretary Frontier Group Holdings, Inc.

NOTICE OF SPECIAL MEETING OF STOCKHOLDERS

To the Stockholders of Spirit Airlines, Inc.:

Spirit Airlines, Inc. (which we refer to as” Spirit”) will hold a special meeting of holders of common stock of Spirit (who we refer to as “Spirit stockholders”) virtually via live webcast on the Internet at www.virtualshareholdermeeting.com/SAVE2022SM, on June 10, 2022, at 9:00 a.m. Eastern Time (which we refer to as the “Spirit special meeting”) to consider and vote upon the following matters:

Spirit has fixed the close of business on May 6, 2022 as the record date for the Spirit special meeting. Only Spirit stockholders of record at that time are entitled to notice of, and to vote at, the Spirit special meeting, or any adjournment or postponement of the Spirit special meeting. During the Spirit special meeting, Spirit stockholders will be able to examine the list of the stockholders entitled to vote at the Spirit special meeting by following the instructions on the live webcast. Approval of the merger proposal requires the affirmative vote of holders of a majority in voting power of the outstanding shares of common stock, $0.0001 par value per share, of Spirit (which we refer to as “Spirit common stock”), entitled to vote on thereon. Approval of each of the compensation proposal and the adjournment proposal requires the affirmative vote of the holders of a majority in voting power of the shares of Spirit common stock which are present in person or by proxy at the Spirit special meeting and entitled to vote thereon.

The board of directors of Spirit (which we refer to as the “Spirit board of directors”) has unanimously adopted the merger agreement, has determined that the merger, on the terms and conditions set forth in the merger agreement, is advisable and in the best interests of Spirit and its stockholders, and unanimously recommends that Spirit stockholders vote “FOR” the merger proposal, “FOR” the compensation proposal and “FOR” the adjournment proposal.

Your vote is very important. Frontier and Spirit cannot complete the merger unless Spirit’s stockholders adopt the merger proposal.

Regardless of whether you plan to attend (via the Internet) the Spirit special meeting, please vote as soon as possible by following the voting procedures described on the proxy card. If you do not vote on the merger proposal, it will have the same effect as a vote by you against the merger proposal.

The enclosed information statement and proxy statement/prospectus provides a detailed description of the Spirit special meeting, the merger, the documents related to the merger and other related matters. We urge you to read the information statement and proxy statement/prospectus, including any documents incorporated in the information statement and proxy statement/prospectus by reference, and its annexes carefully and in their entirety.

BY ORDER OF THE BOARD OF DIRECTORS
		Thomas Canfield Secretary

REFERENCES TO ADDITIONAL INFORMATION

This information statement and proxy statement/prospectus incorporates important business and financial information about Frontier Group Holdings, Inc. (which we refer to as “Frontier”) and Spirit Airlines, Inc. (which we refer to as “Spirit”), from documents filed with the U.S. Securities and Exchange Commission (which we refer to as the “SEC”) that are not included in or delivered with this information statement and proxy statement/prospectus. You can obtain any of the documents filed with or furnished to the SEC by Frontier and/or Spirit at no cost from the SEC’s website at http://www.sec.gov. You may also request copies of these documents, including documents incorporated by reference in this information statement and proxy statement/prospectus, at no cost by contacting the appropriate company at the following address:

You will not be charged for any of these documents that you request. To obtain timely delivery of these documents, Spirit stockholders must request them no later than five business days before the date of the Spirit special meeting. This means that Spirit stockholders requesting documents must do so by June 3, 2022.

You should rely only on the information contained in, or incorporated by reference into, this document. No one has been authorized to provide you with information that is different from that contained in, or incorporated by reference into, this document. This document is dated                 , 2022, and you should assume that the information in this document is accurate only as of such date. You should assume that the information incorporated by reference into this document is accurate as of the date of such document. Neither the mailing of this document to Frontier stockholders or Spirit stockholders, nor the issuance by Frontier of shares of its common stock in connection with the merger, will create any implication to the contrary.

This document does not constitute an offer to sell, or a solicitation of an offer to buy, any securities, or the solicitation of a proxy, in any jurisdiction to or from any person to whom it is unlawful to make any such offer or solicitation in such jurisdiction. Except where the context otherwise indicates, information contained in this document regarding Frontier has been provided by Frontier and information contained in this document regarding Spirit has been provided by Spirit.

Please see “Where You Can Find More Information” for more details.

ABOUT THIS DOCUMENT

Frontier has supplied all information contained in or incorporated by reference into this information statement and proxy statement/prospectus relating to Frontier. Spirit has supplied all information contained in or incorporated by reference into this information statement and proxy statement/prospectus relating to Spirit. Frontier and Spirit have both contributed information relating to the merger.

This information statement and proxy statement/prospectus forms a part of a registration statement on Form S-4 (Registration No. 333-263467) filed by Frontier with the SEC. It constitutes a prospectus of Frontier under Section 5 of the Securities Act of 1933, as amended (which we refer to as the “Securities Act”), and the rules thereunder, with respect to the shares of Frontier common stock to be issued to Spirit stockholders in the merger. It also constitutes a proxy statement under Section 14(a) of the Exchange Act and a notice of meeting and action to be taken with respect to the Spirit special meeting of stockholders at which Spirit stockholders will consider and vote on the proposal to adopt the merger agreement and to approve the transactions contemplated by the merger agreement and the other proposals described in this information statement and proxy statement/prospectus. In addition, it constitutes an information statement under Section 14(c) of the Exchange Act and Section 228(e) of the General Corporation Law of the State of Delaware (which we refer to as the “DGCL”) to provide Frontier stockholders with notice of the Frontier written consent and material information concerning the actions taken in connection with the Frontier written consent.

You should rely only on the information contained in or incorporated by reference into this document. No one has been authorized to provide you with information that is different from that contained in or incorporated by reference into this document. You should not assume that the information contained in any document incorporated by reference herein is accurate as of any date other than the date of such document. Any statement contained in a document incorporated or deemed to be incorporated by reference into this document will be deemed to be modified or superseded to the extent that a statement contained herein or in any other subsequently filed document which also is or is deemed to be incorporated by reference into this document modifies or supersedes that statement. Any statement so modified or superseded will not be deemed, except as so modified or superseded, to constitute a part of this document. Neither the mailing of this document to the stockholders of Spirit, nor the taking of any actions contemplated hereby by Frontier or Spirit at any time will create any implication to the contrary.

This document does not constitute an offer to sell, or a solicitation of an offer to buy, any securities, or the solicitation of a proxy, in any jurisdiction in which or from any person to whom it is unlawful to make any such offer or solicitation in such jurisdiction.

TABLE OF CONTENTS

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QUESTIONS AND ANSWERS

The following are some questions that you may have about the merger and the Spirit special meeting, and brief answers to those questions. We urge you to read carefully the remainder of this information statement and proxy statement/prospectus because the information in this section does not provide all of the information that might be important to you with respect to the merger, or the Spirit special meeting. Additional important information is also contained in the documents incorporated by reference into this information statement and proxy statement/prospectus. Please see “Where You Can Find More Information.”

General

If the merger is completed, Spirit stockholders will receive $2.13 in cash, without interest (which we refer to as the “per share cash consideration”), and 1.9126 shares of Frontier common stock (which we refer to as the “per share stock consideration” and, together with the per share cash consideration, the “merger consideration”) for each share of Spirit common stock (except for treasury stock or shares owned by Frontier) they hold immediately prior to the merger, plus cash in lieu of fractional shares. As a result of the foregoing, based on the fully diluted number of shares of Frontier common stock and Spirit common stock as of February 4, 2022, the last trading day before public announcement of the merger, it is expected that Frontier stockholders will hold approximately 51.5%, and Spirit stockholders will hold approximately 48.5%, of the fully diluted shares of the combined company immediately after the effective time of the merger (which we refer to as the “effective time”).

The merger cannot be completed unless, among other things, Spirit stockholders approve the proposal to adopt the merger agreement.

In order to adopt the merger agreement and related matters, Spirit has called a special meeting of its stockholders (which we refer to as the “Spirit special meeting”). This document serves as the proxy statement for the Spirit special meeting and describes the proposals to be presented at the Spirit special meeting.

Finally, this document is also a prospectus that is being delivered to Spirit stockholders because, in connection with the merger, Frontier will be issuing to Spirit stockholders shares of Frontier common stock as merger consideration.

For Frontier stockholders, this information statement and proxy statement/prospectus contains important information about the merger and the other actions taken in connection with the Frontier written consent (as defined below) and serves as your notice pursuant to Section 228(e) of the DGCL. Frontier is not asking you for a proxy and you are not requested to send Frontier a proxy.

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For Spirit stockholders, this information statement and proxy statement/prospectus contains important information about the merger and the other proposals being voted on at the Spirit special meeting and important information to consider in connection with an investment in Frontier common stock. You should read it carefully and in its entirety. The enclosed materials allow you to have your shares of Spirit common stock voted by proxy without attending the Spirit special meeting. Your vote is important and we encourage you to submit your proxy as soon as possible.

For Frontier Stockholders

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For Spirit Stockholders

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Under the terms of the merger agreement, Spirit will settle any conversions of Spirit convertible notes that occur prior to the effective time (i) pursuant to “Physical Settlement” (as defined in the indenture governing the 2025 convertible notes) for any conversions of 2025 convertible notes and (ii) pursuant to “Cash Settlement” (as defined in the indenture governing the 2026 convertible notes) for any conversions of 2026 convertible notes, in each case pursuant to the terms of the indentures governing the Spirit convertible notes.

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Subject to the limitations and qualifications described in the section entitled “Material U.S. Federal Income Tax Consequences of the Merger” of this information statement and proxy statement/prospectus:

SPIRIT WILL NOT RESOLICIT STOCKHOLDER VOTES IN THE EVENT THAT THE MERGER FAILS TO QUALIFY AS A REORGANIZATION.

For further information, including a discussion of the potential application of Section 304 of the Internal Revenue Code if the merger does not qualify as a reorganization, which may characterize the receipt of cash consideration by certain holders of Spirit common stock as a dividend for U.S. federal income tax purposes, please see the section entitled “Material U.S. Federal Income Tax Consequences of the Merger” beginning on page 164 of this information statement and proxy statement/prospectus.

All holders of Spirit common stock should consult their own tax advisors for a full understanding of the tax consequences of the merger to them in light of their particular facts and circumstances.

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Based on the closing price per share of Frontier common stock on NASDAQ, on February 4, 2022, the last trading day before public announcement of the merger, of $12.39, the per share stock consideration represented approximately $23.70, for a total merger consideration of $25.83 in value for each share of Spirit common stock. Based on the closing price per share of Frontier common stock on May 9, 2022, the latest practicable trading day before the date of this information statement and proxy statement/prospectus, of $8.73, the per share stock consideration represented approximately $16.70, for a total merger consideration of $18.83 in value for each share of Spirit common stock. We urge you to obtain current market quotations for shares of Frontier common stock (trading symbol “ULCC”) and shares of Spirit common stock (currently traded on the New York Stock Exchange, or the NYSE, under the trading symbol “SAVE”).

The procedures for voting are as follows:

Stockholder of Record: Shares Registered in Your Name

If you are a stockholder of record, you may vote at the Spirit special meeting. Alternatively, you may vote by proxy by signing, dating and returning the proxy card, over the Internet or by telephone. Whether or not you plan to attend (via the Internet) the Spirit special meeting, we urge you to vote by proxy to ensure your vote is counted. Even if you have submitted a proxy before the Spirit special meeting, you may still attend

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the Spirit special meeting and vote via the Internet. In such case, your previously submitted proxy will be disregarded.

Beneficial Owner: Shares Registered in the Name of Broker, Bank or Other Agent

If you are a beneficial owner of shares registered in the name of your broker, bank or other agent, you should have received a voting instruction card and voting instructions with these proxy materials from that organization rather than from us. Simply complete and mail the voting instruction card to ensure that your vote is counted. To vote (via the Internet) at the Spirit special meeting, you must obtain a valid proxy from your broker, bank or other agent. Follow the instructions from your broker, bank or other agent included with these proxy materials, or contact your broker, bank or other agent to request a proxy form.

The telephone and Internet voting procedures are designed to authenticate stockholders’ identities, to allow stockholders to give their voting instructions and to confirm that stockholders’ instructions have been recorded properly.

If you hold shares of Spirit common stock entitled to vote at the Spirit special meeting through a bank, brokerage firm or other nominee, you may instruct your bank, brokerage firm or other nominee to vote your shares by following the instructions that the bank, brokerage firm or nominee provides to you. If you do not provide voting instructions to your brokerage firm, your shares of Spirit common stock entitled to vote at the Spirit special meeting will not be voted and will not be treated as present for purposes of establishing a quorum.

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Compensation proposal:

Adjournment proposal:

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For Both Frontier Stockholders and Spirit Stockholders

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Spirit stockholders: If you have any questions concerning the merger or this information statement and proxy statement/prospectus, would like additional copies of this information statement and proxy statement/prospectus, or need help voting your shares of Spirit common stock, please contact Spirit’s proxy solicitor, Okapi Partners LLC, toll-free at (855) 208-8903 or via email at info@okapipartners.com.

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RISK FACTORS

In addition to general investment risks and the other information contained in or incorporated by reference into this information statement and proxy statement/prospectus, including the matters addressed under the section “Cautionary Statement Regarding Forward-Looking Statements,” Frontier’s Annual Report on Form 10-K for the year ended December 31, 2021, and Spirit’s Annual Report on Form 10-K for the year ended December 31, 2021, you should carefully consider the following risk factors in deciding how to vote for the proposals presented in this information statement and proxy statement/prospectus. You should also consider the other information in this information statement and proxy statement/prospectus and the other documents incorporated by reference into this information statement and proxy statement/prospectus. Please see “Where You Can Find More Information.”

Risk Factors Summary

Below is a summary of the principal risk factors that you should consider in deciding how to vote for the proposals presented in this information statement and proxy statement/statement. The below summary is qualified in its entirety by the more complete discussion of such risks and uncertainties that follows this summary.

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Risks Related to the Merger

The pendency of the proposed merger may cause disruption in Frontier and Spirit’s businesses.

On February 5, 2022, Frontier entered into the merger agreement with Spirit and Merger Sub, pursuant to which and subject to the terms and conditions therein, Merger Sub will merge with and into Spirit, with Spirit continuing as the surviving corporation.

The merger agreement restricts Frontier and Spirit from taking specified actions without the other party’s consent until the merger is completed or the merger agreement is terminated. See “The Merger Agreement—Other Covenants” beginning on page 152 for a description of the restrictive covenants applicable to Frontier and Spirit. These restrictions and others more fully described in the merger agreement may affect Frontier and Spirit’s ability to execute their business strategies and attain their financial and other goals and may impact Frontier and Spirit’s businesses, results of operations and financial conditions.

The pendency of the proposed merger could cause disruptions to Frontier and Spirit’s businesses or business relationships, which could have an adverse impact on Frontier and Spirit’s results of operations. Parties with which Frontier or Spirit have business relationships, including customers, unions, employees, suppliers, third-party service providers and third-party distribution channels, may be uncertain as to the future of such relationships and may delay or defer certain business decisions, seek alternative relationships with third parties or seek to alter their present business relationships with Frontier or Spirit. Parties with whom Frontier or Spirit otherwise may have sought to establish business relationships may seek alternative relationships with third parties.

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The pursuit of the merger and the preparation for Spirit’s integration with Frontier’s business is expected to place a significant burden on Frontier and Spirit’s management and internal resources. The diversion of managements’ attention away from day-to-day business concerns and any difficulties encountered in the transition and integration process could adversely affect Frontier and Spirit’s businesses, results of operations and financial conditions.

While the merger is pending, Frontier and Spirit intend to continue to grow their businesses, which will entail the continued hiring of additional employees, including pilots and other skilled workers, presently in short supply in the airline industry. Any disruption or perceived uncertainty may make it more difficult for Frontier and Spirit to meet their employee retention and hiring goals which could materially impact Frontier and Spirit’s businesses, results of operations and financial conditions.

Frontier and Spirit have incurred and will continue to incur significant costs, expenses and fees for professional services and other transaction costs in connection with the merger. Frontier and Spirit may also incur unanticipated costs in connection with Spirit’s integration with Frontier’s business. The substantial majority of these costs will be non-recurring expenses relating to the merger, and many of these costs are payable regardless of whether or not the merger is consummated. Frontier and Spirit could be subject to litigation related to the proposed merger, which could prevent or delay the consummation of the merger and result in significant costs and expenses.

In order to complete the merger, Frontier and Spirit must obtain certain governmental approvals, and if such approvals are not granted or are granted with conditions, completion of the merger will be jeopardized.

Although Frontier and Spirit have agreed to use reasonable best efforts, subject to certain limitations, to make certain governmental filings and obtain the required governmental approvals, including from the FCC, FAA and DOT and the expiration or early termination of the statutory waiting period under the HSR Act, as the case may be, there can be no assurance that the relevant waiting periods will expire or be terminated or that the relevant approvals will be obtained. As a condition to approving the merger, these governmental authorities may impose conditions, terms, obligations or restrictions or require divestitures or place restrictions on the conduct of the combined company’s business after completion of the merger. There can be no assurance that regulators will not challenge the transaction judicially or impose conditions, terms, obligations or restrictions and that such conditions, terms, obligations or restrictions will not have the effect of delaying or preventing completion of the merger or imposing additional material costs on or materially limiting the revenues of the combined company following the merger, or otherwise adversely affecting, including to a material extent, the combined company’s business, results of operations and financial condition after completion of the merger. If Frontier or Spirit is required to divest assets or businesses, there can be no assurance that Frontier or Spirit will be able to negotiate such divestitures expeditiously or on favorable terms or that the governmental authorities will approve the terms of such divestitures. Neither Frontier nor Spirit can provide assurance that these conditions, terms, obligations or restrictions will not result in the abandonment of the merger.

Uncertainties associated with the merger may cause a loss of management personnel and other key employees which could adversely affect the future business and operations of the combined company.

Frontier and Spirit are dependent on the experience and industry knowledge of their respective officers and other key employees to execute their business plans. The combined company’s success after the merger will depend in part upon the ability of Frontier and Spirit to retain key management personnel and other key employees. Current and prospective employees of Frontier and Spirit may experience uncertainty about their roles within the combined company following the merger, which may have an adverse effect on the ability of each of Frontier and Spirit to attract or retain key management and other key personnel. Accordingly, no assurance can be given that the combined company will be able to attract or retain key management personnel and other key employees of Frontier and Spirit to the same extent that Frontier and Spirit have previously been able to attract or retain their own employees.

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Failure to complete the merger in a timely manner or at all could negatively impact the market price of Frontier and Spirit’s common stock, as well as Frontier and Spirit’s future businesses and their results of operations and financial conditions.

The merger cannot be completed until conditions to closing are satisfied or (if permissible under applicable law) waived. The merger is subject to numerous closing conditions, including among other things, (i) approval of the transactions by Spirit’s stockholders, (ii) receipt of applicable regulatory approvals, including approvals from the FCC, FAA and DOT and the expiration or early termination of the statutory waiting period under the HSR Act and other required regulatory approvals; (iii) the absence of any law or order prohibiting the consummation of the transactions; (iv) the effectiveness of the registration statement to be filed by Frontier and Spirit with the SEC pursuant to the merger agreement; (v) the authorization and approval for listing on The Nasdaq Stock Market LLC of the shares of Frontier common stock to be issued to holders of Spirit’s common stock in the merger; and (vi) the absence of any material adverse effect (as defined in the merger agreement) on either Frontier or Spirit.

The process of satisfying such conditions, including seeking the necessary regulatory approvals, could delay the completion of the merger for a significant period of time or prevent it from occurring. Further, there can be no assurance that the conditions to the closing of the merger will be satisfied or waived or that the merger will be completed.

If the merger is not completed in a timely manner or at all, Frontier and Spirit’s ongoing businesses may be adversely affected as follows:

If the merger is not consummated, there can be no assurance that these risks will not materialize and will not materially adversely affect Frontier or Spirit’s stock price, business, results of operations and financial condition.

For a discussion of the conditions to closing, please see “The Merger Agreement—Conditions to Completion of the Merger” beginning on page 157 of this information statement and proxy statement/prospectus.

The ability of the merger to qualify as a “reorganization” within the meaning of Section 368(a) of the Internal Revenue Code will not be known until closing, the completion of the merger is not conditioned on the receipt of an opinion of counsel to the effect that the merger will qualify as a reorganization, and neither Spirit nor Frontier intends to request a ruling from the Internal Revenue Service regarding the U.S. federal income tax consequences of the merger.

As described in the section entitled “Material U.S. Federal Income Tax Consequences of the Merger”, it will not be known at the time of the special meeting whether the merger will qualify as a “reorganization” within the meaning of Section 368(a) of the Internal Revenue Code. Qualification of the merger as a reorganization depends on compliance with numerous technical requirements, including that the value of the shares of Frontier common stock issued to holders of Spirit common stock in the merger, determined as of completion of the merger, represents at least 80 percent of the total consideration paid to holders of Spirit common stock in the merger. This determination depends on facts that will not be known until the completion of the merger (e.g., the value of Frontier common stock as of such time). The completion of the merger is not conditioned on the merger

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qualifying as a reorganization or upon the receipt of an opinion of counsel to that effect, and neither Spirit nor Frontier intends to request a ruling from the Internal Revenue Service regarding the U.S. federal income tax consequences of the merger. Accordingly, no assurance can be given that the merger will qualify as a reorganization.

SPIRIT WILL NOT RESOLICIT STOCKHOLDER VOTES IN THE EVENT THAT THE MERGER FAILS TO QUALIFY AS A REORGANIZATION.

You should read the section entitled “Material U.S. Federal Income Tax Consequences of the Merger” beginning on page 164 of this information statement and proxy statement/prospectus and consult your own tax advisors regarding the U.S. federal income tax consequences of the merger to you in light of your particular facts and circumstances.

Risks Relating to Ownership of Frontier Common Stock

The merger consideration is fixed and will not be adjusted. Because the market price of Frontier common stock may fluctuate, Spirit stockholders cannot be sure of the market value of the stock consideration they will receive in exchange for their shares of Spirit common stock in connection with the transactions.

In connection with the merger, at the effective time, each share of Spirit common stock (other than shares held by Frontier, Spirit or their respective subsidiaries immediately prior to the effective time and shares as to which dissenters’ rights have been properly perfected) will be converted into the right to receive (i) 1.9126 shares of Frontier common stock and (ii) $2.13 in cash, without interest. Accordingly, the market value of the stock consideration that Spirit stockholders will receive will vary based on the price of Frontier common stock at the time Spirit stockholders receive the merger consideration. The market price of Frontier common stock may decline after the date of this document, after Spirit stockholders exchange their shares and/or after the closing.

A decline in the market price of Frontier common stock could result from a variety of factors beyond Frontier’s control, including, among other things, the possibility that Frontier may not achieve the expected benefits of the acquisition of Spirit as rapidly or to the extent anticipated, Spirit’s business may not perform as anticipated following the closing, the effect of Frontier’s acquisition of Spirit on Frontier’s financial results may not meet the expectations of Frontier, financial analysts or investors, or the addition and integration of Spirit’s business may be unsuccessful, may take longer or be more disruptive than anticipated, as well as numerous factors affecting Frontier and its businesses that are unrelated to Spirit.

If the merger is completed, there will be a lapse of time between each of the date of this information statement and proxy statement/prospectus, the date on which Spirit stockholders vote to approve the Spirit merger proposal and the date on which Spirit stockholders entitled to receive the merger consideration actually receive the merger consideration. The market value of shares of Frontier common stock may decline during and after these periods as a result of a variety of factors, and consequently, at the time Spirit stockholders must decide whether to adopt the merger proposal, they will not know the actual market value of any merger consideration they will receive when the merger is completed. The actual value of any merger consideration received by Spirit stockholders at the completion of the merger will depend on the market value of the shares of Frontier common stock at that time.

The market price of the Frontier common stock may be volatile.

The market price of the Frontier common stock may fluctuate significantly due to a variety of factors, some of which are beyond Frontier’s and Spirit’s control, including:

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The value of Frontier’s common stock may be materially adversely affected by additional issuances of common stock or preferred stock by Frontier or sales by Frontier’s principal stockholder.

Any future issuances or sales of Frontier’s common stock by Frontier will be dilutive to Frontier’s common stockholders. Frontier had 217,065,096 shares of common stock outstanding as of December 31, 2021. All of the shares of common stock sold in Frontier’s initial public offering are freely tradable without restrictions or further registration under the Securities Act. Indigo Fund, an investment fund managed by Indigo Partners LLC (which we refer to as “Indigo Partners”), is the holder of approximately 178.8 million shares of Frontier’s common stock as of December 31, 2021, and is entitled to rights with respect to registration of all such shares under the Securities Act pursuant to a registration rights agreement. Sales of substantial amounts of Frontier’s common stock in the public or private market, a perception in the market that such sales could occur or the issuance of securities exercisable or convertible into Frontier’s common stock, could adversely affect the prevailing price of Frontier’s common stock.

If securities or industry analysts do not publish research or reports about Frontier’s business or publish negative reports about Frontier’s business, Frontier’s stock price and trading volume could decline.

The trading market for Frontier’s common stock depends in part on the research and reports that securities and industry analysts may publish about Frontier or Frontier’s business. If one or more of the analysts who cover Frontier downgrade Frontier’s stock or publish inaccurate or unfavorable research about Frontier’s business, the trading price of Frontier’s common stock would likely decline. If one or more of these analysts ceases to cover Frontier or fails to publish reports on Frontier regularly, demand for Frontier’s stock could decrease, which may cause the trading price of Frontier’s common stock and the trading volume of Frontier’s common stock to decline.

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The issuance or sale of shares of Frontier’s common stock, or rights to acquire shares of Frontier’s common stock, or the exercise of the warrants issued to the U.S. Department of the Treasury, could depress the trading price of Frontier’s common stock.

Frontier may conduct future offerings of its common stock, preferred stock or other securities that are convertible into, or exercisable for, Frontier’s common stock to finance its operations or fund acquisitions, or for other purposes. In connection with Frontier’s participation in the Payroll Support Program under the CARES Act, Frontier issued warrants to the U.S. Department of the Treasury (which we refer to as the “Treasury”), which are exercisable for up to an aggregate of 759,850 shares of Frontier’s common stock.

In connection with the $150 million borrowing under the loan received from the Treasury, Frontier issued warrants to the Treasury which are exercisable for up to 2,358,090 shares of Frontier’s common stock. Further, Frontier reserves shares of its common stock for future issuance under its equity incentive plans, which shares are eligible for sale in the public market to the extent permitted by the provisions of various agreements and, to the extent held by affiliates, the volume and manner of sale restrictions of Rule 144. If these additional shares are sold, or if it is perceived that they will be sold, into the public market, the price of Frontier’s common stock could decline substantially. If Frontier issues additional shares of its common stock or rights to acquire shares of its common stock, if any of Frontier’s existing stockholders sells a substantial amount of Frontier’s common stock or if the market perceives that such issuances or sales may occur, then the trading price of Frontier’s common stock may significantly decline. In addition, Frontier’s issuance of additional shares of common stock will dilute the ownership interests of Frontier’s existing common stockholders.

The market price of Frontier common stock after the merger may be affected by factors different from those currently affecting the shares of Spirit.

At the effective time, holders of Spirit common stock will become holders of Frontier common stock. Spirit’s business prior to the merger is independent of and different from that of Frontier, and accordingly the results of operations of Frontier may be affected by factors different from those currently affecting the results of operations of Spirit. Following the completion of the merger, Spirit will be part of a larger company, so decisions affecting Spirit may be made in respect of the larger combined business as a whole rather than the Spirit business individually. For additional information on the business of Spirit and a discussion of certain factors to consider in connection with its business, see the documents relating to Spirit that are incorporated by reference by Spirit into this information statement and proxy statement/prospectus. Please see the section entitled “Where You Can Find More Information” beginning on page 204 of this information statement and proxy statement/prospectus for the location of information incorporated by reference into this information statement and proxy statement/prospectus.

Any damage to our reputation or brand image could adversely affect the market price of Frontier common stock.

Maintaining a good reputation globally is critical to our business. Our reputation or brand image could be adversely impacted by, among other things, any failure to maintain high ethical, social and environmental sustainability practices for all of our operations and activities; our impact on the environment; any inability to maintain our position as “America’s Greenest Airline” including, for example, if another major U.S. airline experiences more average fuel savings than us based on ASMs per fuel gallon consumed or if consumers perceive us to be less “green” than other airlines based on different factors or metrics or by attributing the sustainability practices of our vendors, suppliers and other third parties to us; public pressure from investors or policy groups to change our policies, such as movements to institute a “living wage;” customer perceptions of our advertising campaigns, sponsorship arrangements or marketing programs; customer perceptions of our use of social media; or customer perceptions of statements made by us, our employees and executives, agents or other third parties. In addition, we operate in a highly visible industry that has significant exposure to social media. Negative publicity, including as a result of misconduct by our customers, vendors or employees, can spread

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rapidly through social media. Should we not respond in a timely and appropriate manner to address negative publicity, our brand and reputation may be significantly harmed. Damage to our reputation or brand image or loss of customer confidence in our services could adversely affect our business and financial results and market price of Frontier common stock, as well as require additional resources to rebuild our reputation.

In addition, our reputation or brand image could be adversely impacted by any inability to deliver strong operational performance, which we believe helps strengthen our customer loyalty and attract new customers. The DOT publishes statistics regarding measures of customer satisfaction for domestic airlines, including on-time performance and completion factor. Our on-time performance, which measures the percentage of our scheduled flights that were operated by us that were on-time (within 15 minutes) for domestic routes only, was 76.6%, 83.9%, and 73.1% for the years ended December 31, 2021, 2020, and 2019, respectively. Our completion factor, which measures the percentage of our scheduled flights that were completed by us for domestic routes only, whether or not delayed (i.e., not cancelled), was 98.6%, 94.9%, and 98.3% for the years ended December 31, 2021, 2020, and 2019, respectively. The ranges of on-time performance and completion factor for the 10 airlines of significant size in the United States ranged from 68.3% to 90.1% and 96.7% to 99.6%, respectively, and we ranked 7th and 3rd, respectively, for the year ended December 31, 2021. Any sustained inability to maintain or improve our operational performance could result in decreased customer loyalty and, in turn, could significantly harm our brand and reputation and adversely affect our business and financial results, and the market price of Frontier common stock.

Moreover, the outbreak and spread of COVID-19 has adversely impacted consumer perceptions of the health and safety of travel, and airline travel in particular, and these negative perceptions, whether or not based in fact, could continue even after the pandemic subsides. Actual or perceived risk of infection on our flights has had, and may continue to have, a material adverse effect on the public’s perception of us, which has harmed, and may continue to harm, our reputation and business. We have taken various measures to reassure our team members and the traveling public of the safety of air travel, such as requiring that facial coverings must be worn by all customers and team members throughout every flight and introducing a fogging disinfectant to our already stringent aircraft cleaning and sanitation protocols. We expect that we will continue to incur COVID-19-related costs as we sanitize aircraft, implement additional hygiene-related protocols and take other actions to limit the threat of infection among our employees and passengers. However, we cannot assure you that these or any other actions we might take in response to the COVID-19 pandemic will be sufficient to restore the confidence of consumers in the safety of air travel.

Spirit stockholders will have a reduced ownership and voting interest in Frontier as compared to their ownership and voting interest in Spirit and will exercise less influence over management.

Currently, Spirit stockholders have the right to vote in the election of the Spirit board of directors and the power to approve or reject any matters requiring stockholder approval under Delaware law and the Spirit certificate of incorporation and bylaws. Upon completion of the merger, each Spirit stockholder who receives shares of Frontier common stock will become a stockholder of Frontier with a percentage ownership of Frontier that is smaller than the Spirit stockholder’s current percentage ownership of Spirit. Based on the fully diluted number of shares of Frontier common stock and shares of Spirit common stock as of May 6, 2022 and the exchange ratio of 1.9126, after the merger Spirit stockholders are expected to become owners of approximately 48.8% of the fully diluted shares of Frontier common stock, without giving effect to any shares of Frontier common stock held by Spirit stockholders prior to the completion of the merger and disregarding stock options, restricted stock units and other equity awards or rights to acquire shares that may be issued by Frontier or Spirit pursuant to any employee stock plan.

Consequently, even if all former Spirit stockholders voted together on all matters presented to Frontier stockholders from time to time, the former Spirit stockholders would exercise significantly less influence over Frontier after the completion of the merger relative to their influence over Spirit prior to the completion of the merger, and thus would have a less significant impact on the approval or rejection of future Frontier proposals submitted to a stockholder vote.

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The shares of Frontier common stock to be received by Spirit stockholders as a result of the merger will have different rights from the shares of Spirit common stock.

At the effective time, Spirit stockholders will become holders of Frontier common stock and their rights as stockholders will be governed by Frontier’s Amended and Restated Certificate of Incorporation and Amended and Restated Bylaws. The rights associated with Spirit common stock are different from the rights associated with Frontier common stock.

For a discussion of the different rights associated with Frontier common stock, see the sections entitled “Description of Capital Stock of Frontier” beginning on page 185 and “Comparison of Frontier Stockholders’ and Spirit Stockholders’ Rights” beginning on page 192 of this information statement and proxy statement/prospectus.

Spirit stockholders will be forfeiting all rights with respect to their shares of Spirit common stock other than the right to receive the merger consideration, including the right to participate directly in any earnings or future growth of Spirit.

If the merger is completed, Spirit stockholders will cease to have any equity interest in Spirit and will not participate in its earnings or any future growth, except indirectly through ownership of Frontier shares received as part of the merger consideration.

Spirit directors and officers potentially have interests in the transaction that differ from, or are in addition to, the interests of Spirit stockholders generally.

Some of the officers and directors of Spirit may be deemed to have interests in the mergers that are different from, or in addition to, the interests of Spirit stockholders. These interests may include, among others, agreements that certain officers have entered into with Spirit that provide for the acceleration of Spirit RSU Awards and Spirit 2022 PSU Awards in the event the officer experiences a qualifying termination of employment within a specified period following a change of control of Spirit, and cash severance payments and/or other benefits under Spirit’s 2017 Executive Severance Plan that may be payable to Spirit’s executive officers upon a termination without cause or for good reason in connection with the merger.

For additional information, see “The Mergers—Interests of Spirit’s Directors and Executive Officers in the Mergers” and “The Merger Agreement—Employee Matters.”

Failure to complete the merger could negatively impact the price of shares of Frontier common stock and the price of shares of Spirit common stock, as well as Frontier’s and Spirit’s respective future businesses and financial results.

The merger agreement contains a number of conditions that must be satisfied or waived prior to the completion of the merger, which are described in the section entitled “The Merger Agreement—Conditions to Complete the Merger.” There can be no assurance that all of the conditions to the merger will be so satisfied or waived. If these conditions are not satisfied or waived, Frontier and Spirit will be unable to complete the merger.

If the merger is not completed for any reason, including the failure to receive the Spirit stockholder approval, Frontier’s and Spirit’s respective businesses and financial results may be adversely affected, including as follows:

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In addition to the above risks, if the merger agreement is terminated and either party’s board seeks an alternative transaction, such party’s stockholders cannot be certain that such party will be able to find a party willing to engage in a transaction on more attractive terms than the merger.

Frontier’s anti-takeover provisions may delay or prevent a change of control, which could adversely affect the price of Frontier’s common stock.

Frontier’s amended and restated certificate of incorporation and amended and restated bylaws may make it difficult to remove Frontier’s board of directors and management and may discourage or delay “change of control” transactions, which could adversely affect the price of Frontier’s common stock. These provisions include, among others:

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Certain anti-takeover provisions under Delaware law also apply to Frontier. While Frontier has elected not to be subject to the provisions of Section 203 of the DGCL in its amended and restated certificate of incorporation, such certificate of incorporation provides that in the event Indigo Fund and its affiliates cease to beneficially own at least 15% of the then-outstanding shares of Frontier’s voting common stock, Frontier will automatically become subject to Section 203 of the DGCL to the extent applicable. Under Section 203, a corporation may not, in general, engage in a business combination with any holder of 15% or more of its voting stock unless the holder has held the stock for three years or, among other things, the board of directors has approved the transaction.

Frontier’s amended and restated certificate of incorporation and amended and restated bylaws provide for an exclusive forum in the Court of Chancery of the State of Delaware for certain disputes between Frontier and its stockholders, and that the federal district courts of the United States will be the exclusive forum for the resolution of any complaint asserting a cause of action under the Securities Act of 1933.

Frontier’s amended and restated certificate of incorporation and amended and restated bylaws provide that: (i) unless Frontier consents in writing to the selection of an alternative forum, the Court of Chancery of the State of Delaware (or, if such court does not have subject matter jurisdiction thereof, the federal district court of the State of Delaware) will, to the fullest extent permitted by law, be the sole and exclusive forum for: (A) any derivative action or proceeding brought on Frontier’s behalf, (B) any action asserting a claim for or based on a breach of a fiduciary duty owed by any of Frontier’s current or former directors, officers, other employees, agents or stockholders to Frontier or Frontier’s stockholders, including without limitation a claim alleging the aiding and abetting of such a breach of fiduciary duty, (C) any action asserting a claim against Frontier or any of its current or former directors, officers, employees, agents or stockholders arising pursuant to any provision of the DGCL or Frontier’s amended and restated certificate of incorporation or amended and restated bylaws or as to which the DGCL confers jurisdiction on the Court of Chancery of the State of Delaware, or (D) any action asserting a claim related to or involving Frontier that is governed by the internal affairs doctrine; (ii) unless Frontier consents in writing to the selection of an alternative forum, the federal district courts of the United States will, to the fullest extent permitted by law, be the sole and exclusive forum for the resolution of any complaint asserting a cause or causes of action arising under the Securities Act, and the rules and regulations promulgated thereunder, including all causes of action asserted against any defendant to such complaint; (iii) any person or entity purchasing or otherwise acquiring or holding any interest in Frontier’s shares of capital stock will be deemed to have notice of and consented to these provisions; and (iv) failure to enforce the foregoing provisions would cause Frontier irreparable harm, and Frontier will be entitled to equitable relief, including injunctive relief and specific performance, to enforce the foregoing provisions. This provision is intended to benefit and may be enforced by Frontier, Frontier’s officers and directors, the underwriters to any offering giving rise to such complaint and any other professional entity whose profession gives authority to a statement made by that person or entity and who has prepared or certified any part of the documents underlying the offering. This exclusive forum provision will not apply to suits brought to enforce any liability or duty created by the Exchange Act of 1934, as amended (which we refer to as the “Exchange Act”), or any other claim for which the federal courts have exclusive jurisdiction. Nothing in Frontier’s amended and restated certificate of incorporation or amended and restated bylaws precludes stockholders that assert claims under the Exchange Act from bringing such claims in federal court to the extent that the Exchange Act confers exclusive federal jurisdiction over such claims, subject to applicable law.

Frontier believes these provisions may benefit Frontier by providing increased consistency in the application of Delaware law and federal securities laws by chancellors and judges, as applicable, particularly experienced in resolving corporate disputes, efficient administration of cases on a more expedited schedule relative to other forums and protection against the burdens of multi-forum litigation. If a court were to find the choice of forum provision that is contained in Frontier’s amended and restated certificate of incorporation or amended and restated bylaws to be inapplicable or unenforceable in an action, Frontier may incur additional costs associated with resolving such action in other jurisdictions, which could materially adversely affect Frontier’s business, results of operations, and financial condition. For example, Section 22 of the Securities Act creates concurrent jurisdiction for federal and state courts over all suits brought to enforce any duty or liability created by the

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Securities Act or the rules and regulations thereunder. Accordingly, there is uncertainty as to whether a court would enforce such a forum selection provision as written in connection with claims arising under the Securities Act.

The choice of forum provisions may limit a stockholder’s ability to bring a claim in a judicial forum that it finds favorable for disputes with Frontier or any of Frontier’s current or former directors, officers, other employees, agents or stockholders, which may discourage such claims against Frontier or any of Frontier’s current or former directors, officers, other employees, agents or stockholders and result in increased costs for investors to bring a claim.

Frontier’s amended and restated certificate of incorporation contains a provision renouncing Frontier’s interest and expectancy in certain corporate opportunities.

Frontier’s amended and restated certificate of incorporation provides for the allocation of certain corporate opportunities between Frontier and Indigo Fund. Under these provisions, neither Indigo Fund, its portfolio companies, funds or other affiliates, nor any of their agents, stockholders, members, partners, officers, directors and employees will have any duty to refrain from engaging, directly or indirectly, in the same business activities, similar business activities or lines of business in which Frontier operates. For instance, a director of Frontier who also serves as a stockholder, member, partner, officer, director or employee of Indigo Fund or any of its portfolio companies, funds or other affiliates may pursue certain acquisitions or other opportunities that may be complementary to Frontier’s business and, as a result, such acquisitions or other opportunities may not be available to Frontier. These potential conflicts of interest could have a material adverse effect on Frontier’s business, results of operations or financial condition, if attractive corporate opportunities are allocated by Indigo Fund to itself or its portfolio companies, funds or other affiliates instead of to Frontier. In addition, Frontier’s amended and restated certificate of incorporation provides that Frontier shall indemnify each the aforementioned parties in the event of any claims for breach of fiduciary or other duties brought in connection with such other opportunities.

Frontier’s amended and restated certificate of incorporation and amended and restated bylaws include provisions limiting ownership, control and voting by non-U.S. citizens.

To comply with restrictions imposed by federal law on foreign ownership and control of U.S. airlines, Frontier’s amended and restated certificate of incorporation and amended and restated bylaws restrict ownership, voting and control of shares of Frontier’s common stock by non-U.S. citizens. The restrictions imposed by federal law and DOT policy require that Frontier be owned and controlled by U.S. citizens; that no more than 25.0% of Frontier’s voting stock be owned or controlled, directly or indirectly, by persons or entities who are not U.S. citizens, as defined in 49 U.S.C. § 40102(a)(15); that Frontier’s president, chief executive officer, if any, chairman of the board and at least two-thirds of the members of Frontier’s board of directors and other managing officers be U.S. citizens; that Frontier be under the actual control of U.S. citizens; and, subject to the limitation that no more than 25.0% of Frontier’s voting stock be owned or controlled, directly or indirectly, by persons or entities who are not U.S. citizens, up to 49% of Frontier’s outstanding stock may be owned or controlled, directly or indirectly, by persons or entities who are not U.S. citizens but only if those non-U.S. citizens are from countries that have entered into “open skies” air transport agreements with the U.S. which allow unrestricted access between the United States and the applicable foreign country and to points beyond the foreign country on flights serving the foreign country. Frontier’s amended and restated certificate of incorporation and amended and restated bylaws provide that the failure of non-U.S. citizens to register their shares on a separate stock record, which Frontier refers to as the “foreign stock record,” would result in a loss of their voting rights. Additionally, in no event shall such shares owned or controlled by a non-U.S. citizen be voted if the aggregate foreign ownership of the outstanding common stock exceeds the foreign ownership restrictions imposed by federal law. Frontier’s amended and restated bylaws further provide that no shares of Frontier’s common stock will be registered on the foreign stock record if the amount so registered would exceed the foreign ownership restrictions imposed by federal law. If it is determined that the amount registered in the foreign stock record exceeds the

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foreign ownership restrictions imposed by federal law, shares will be removed from the foreign stock record, resulting in the loss of voting rights, in reverse chronological order based on the date of registration therein, until the number of shares registered therein does not exceed the foreign ownership restrictions imposed by federal law. Frontier is currently in compliance with these ownership restrictions.

Frontier is a holding company and relies on dividends, distributions and other payments, advances and transfers of funds from its subsidiaries to meet its obligations.

Frontier is a holding company that does not conduct any business operations of its own. As a result, Frontier is largely dependent upon cash dividends and distributions and other transfers, including for payments in respect of indebtedness, at the holding company level from its subsidiaries to meet its obligations. The agreements governing the indebtedness of Frontier’s subsidiaries, including the CARES Act, impose restrictions on Frontier’s subsidiaries’ ability to pay dividend distributions or other transfers to Frontier. Each of Frontier’s subsidiaries is a distinct legal entity, and under certain circumstances legal and contractual restrictions may limit Frontier’s ability to obtain cash from them. The deterioration of the earnings from, or other available assets of, Frontier’s subsidiaries for any reason could also limit or impair their ability to pay dividends or other distributions to Frontier.

Risks Relating to the Combined Company Following the Merger

Although Frontier and Spirit expect that the merger will result in synergies and other benefits, the combined company may not realize those benefits because of difficulties related to integration, the achievement of such synergies and other challenges.

Frontier and Spirit have operated and, until completion of the merger, will continue to operate, independently, and there can be no assurances that Frontier’s and Spirit’s businesses can be combined in a manner that allows for the achievement of substantial benefits. Historically, the integration of separate airlines has often proven to be more time consuming, to cost more and to require more resources than initially estimated. The combined company must devote significant management attention and financial and other resources to integrating business practices, cultures and operations. If the combined company is not able to successfully integrate Spirit’s business with Frontier’s, the anticipated benefits, including synergies, of the merger may not be realized fully or may take longer than expected to be realized. Specifically, the following issues, among others, must be addressed in combining Spirit’s operations with Frontier’s in order to realize the anticipated benefits of the merger:

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Even if the operations of Frontier’s business and Spirit’s business are integrated successfully, the full benefits of the merger may not be realized, including, among others, the synergies that are expected. These benefits may not be achieved within the anticipated time frame or at all. Additional unanticipated costs, which could be material, may also be incurred in the integration of Spirit’s business and Frontier’s business. Further, it is possible that there could be loss of key Frontier or Spirit employees, loss of customers, disruption of either or both of Frontier or Spirit’s ongoing businesses or unexpected issues, higher than expected costs and an overall post-completion process that takes longer than originally anticipated.

Frontier plans to submit to the FAA a transition plan for merging the day-to-day operations of Frontier and Spirit under a single operating certificate. The issuance of a single operating certificate will occur when the FAA agrees that the combined company has achieved a level of integration that can be safely managed under one certificate. The actual time required and cost incurred to receive this approval cannot be predicted. Any delay in the grant of such approval or increase in costs beyond those presently expected could have a material adverse effect on the completion date of the combined company’s integration plan and receipt of the benefits expected from that plan. All of these factors could materially adversely affect Frontier’s business, results of operations and financial condition.

The combined company faces challenges in integrating Frontier and Spirit’s computer, communications and other technology systems.

Among the principal risks of integrating Frontier and Spirit’s businesses and operations are the risks relating to integrating various computer, communications and other technology systems, including designing and implementing an integrated customer reservations system, that will be necessary to operate Frontier and Spirit as a single airline and to achieve cost synergies by eliminating redundancies in the businesses. The integration of these systems in a number of prior airline mergers has taken longer, been more disruptive and cost more than originally forecasted. The implementation process to integrate these various systems will involve a number of risks that could adversely impact the combined company’s business, results of operations and financial condition. The related implementation will be a complex and time-consuming project involving substantial expenditures for implementation consultants, system hardware, software and implementation activities, as well as the transformation of business and financial processes.

As with any large project, there will be many factors that may materially affect the schedule, cost and execution of the integration of Frontier and Spirit’s computer, communications and other technology systems. These factors include, among others: problems during the design, implementation and testing phases; systems delays and/or malfunctions; the risk that suppliers and contractors will not perform as required under their contracts; the diversion of management attention from daily operations to the project; reworks due to unanticipated changes in business processes; challenges in simultaneously activating new systems throughout the combined company’s global network; difficulty in training employees in the operations of new systems; the risk of security breach or disruption; and other unexpected events beyond the combined company’s control. The combined company cannot assure that its security measures, change control procedures or disaster recovery plans will be adequate to prevent disruptions or delays. Disruptions in or changes to these systems could result in a disruption to the combined company’s business and operations and the loss of important data. Any of the foregoing could result in a material adverse effect on the combined company’s business, results of operations and financial condition.

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The future results of the combined company will suffer if it does not effectively manage its expanded operations following the merger.

Following the merger, the size of the business of the combined company will increase significantly beyond the current size of either Frontier or Spirit’s business. The combined company’s future success depends, in part, upon its ability to manage this expanded business, which will pose substantial challenges for management, including challenges related to the management and monitoring of new operations and associated increased costs and complexity. There can be no assurances that the combined company will be successful or that it will realize the expected operating efficiencies, cost savings, revenue enhancements and other benefits currently anticipated from the merger.

The combined company is expected to incur substantial expenses related to the merger and the integration of Frontier and Spirit.

The combined company is expected to incur substantial expenses in connection with the merger and the integration of Frontier and Spirit. There are a large number of processes, policies, procedures, operations, technologies and systems that must be integrated, including purchasing, accounting and finance, sales, payroll, pricing, revenue management, reservations, maintenance, flight operations, marketing and benefits. While Frontier and Spirit have assumed that a certain level of expenses would be incurred, there are many factors beyond their control that could affect the total amount or the timing of the integration expenses. Moreover, many of the expenses that will be incurred are, by their nature, difficult to estimate accurately. These expenses could, particularly in the near term, exceed the savings that the combined company expects to achieve from the elimination of duplicative expenses and the realization of economies of scale and cost savings. These integration expenses likely will result in the combined company taking significant charges against earnings following the completion of the merger, and the amount and timing of such charges are uncertain at present.

Uncertainties associated with the merger may cause a loss of management personnel and other key employees which could adversely affect the future business and operations of the combined company.

Frontier and Spirit are dependent on the experience and industry knowledge of their respective officers and other key employees to execute their respective business plans. The combined company’s success after the merger will depend in part upon the ability of Frontier and Spirit to retain key management personnel and other key employees. Current and prospective employees of Frontier and Spirit may experience uncertainty about their roles within the combined company following the merger, which may have an adverse effect on the ability of each of Frontier and Spirit to attract or retain key management and other key personnel. Accordingly, no assurance can be given that the combined company will be able to attract or retain key management personnel and other key employees of Frontier and Spirit to the same extent that Frontier and Spirit have previously been able to attract or retain their own employees.

The unaudited pro forma condensed combined financial statements and the forecasts included in this information statement and proxy statement/prospectus are presented for illustrative purposes only and may not be an indication of the combined company’s financial condition or results of operations after the merger.

The unaudited pro forma condensed combined financial statements and the forecasts contained in this information statement and proxy statement/prospectus are presented for illustrative purposes only and are based on various adjustments, assumptions, and preliminary estimates or are projected to be realized by the combined company after the closing. Consequently, the unaudited pro forma condensed combined financial statements and the forecasts contained in this information statement and proxy statement/prospectus may not be an indication of the combined company’s financial condition or results of operations following the closing for a number of reasons. The actual financial condition and results of operations of the combined company following the closing may not be consistent with, or evident from, these unaudited pro forma condensed combined financial statements and the forecasts. In addition, the assumptions used in preparing the unaudited pro forma condensed combined financial statements and

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the forecasts may not prove to be accurate, and other factors, some of which are not known at the present time, may affect the combined company’s financial condition or results of operations following the closing. Any potential deterioration in Frontier or Spirit’s financial condition or results of operations may cause significant variation in the price of Frontier common stock following the closing. For more information, see “The Merger—Unaudited Prospective Financial Information” beginning on page 73 and “Unaudited Pro Forma Condensed Combined Financial Information” beginning on page 171 of this information statement and proxy statement/prospectus.

Following the closing, the combined company will be bound by all of the obligations and liabilities of both Frontier and Spirit.

Following the closing, the combined company will become bound by all of the obligations and liabilities of Frontier and Spirit. Neither Frontier nor Spirit can predict their respective financial condition at the time of that combination or the ability of the combined company to satisfy its obligations and liabilities.

The combined company could experience significant operating losses in the future.

For a number of reasons, including those addressed in these “Risk Factors,” the combined company might fail to achieve profitability and might experience significant losses. In particular, the condition of the economy and the high volatility of the COVID-19 pandemic have had, and continue to have, an impact on each of Frontier and Spirit’s businesses, financial conditions, and results of operations, and increase the risk that Frontier and Spirit will experience losses in the future.

The demand for airline services is highly sensitive to changes in economic conditions, and another recession or similar economic downturn in the United States or globally would further weaken demand for the combined company’s services and have a material adverse effect on the combined company’s business, results of operations and financial condition, particularly since a substantial portion of the combined company’s customers travel for leisure or other non-essential purposes.

The demand for travel services is affected by U.S. and global economic conditions. Unfavorable economic conditions, such as those resulting from an inflationary economic environment, reactions to the COVID-19 pandemic or military conflict (such as the conflict involving Russia and Ukraine), have historically impaired airline economics. For most cost-conscious leisure travelers, travel is a discretionary expense, and though Frontier and Spirit believe ultra low-cost carriers (which we refer to as “ULCCs”) are best suited to attract travelers during periods of unfavorable economic conditions as a result of such carriers’ low base fares, travelers have often elected to replace air travel at such times with various other forms of ground transportation or have opted not to travel at all. Likewise, during periods of unfavorable economic conditions, businesses have deferred air travel or forgone it altogether. Travelers have also reduced spending by purchasing fewer non-fare services, which can result in a decrease in average revenue per passenger. Because airlines typically have relatively high fixed costs as a percentage of total costs, much of which cannot be mitigated during periods of lower demand for air travel, the airline business is particularly sensitive to changes in U.S. and global economic conditions. A reduction in the demand for air travel due to unfavorable economic conditions would limit the combined company’s ability to raise fares to counteract increased fuel, labor and other costs. If U.S. or global economic conditions are unfavorable or uncertain for an extended period of time, it would have a material adverse effect on the combined company’s business, results of operations and financial condition. In particular, the ongoing COVID-19 pandemic and associated decline in economic activity and increase in unemployment levels have had, and may continue to have, a severe and prolonged effect on the global economy generally and, in turn, may continue to depress demand for air travel into the foreseeable future. Due to the uncertainty surrounding the duration and severity of the COVID-19 pandemic, neither Frontier nor Spirit can provide assurance as to when and at what pace demand for air travel will return to pre-pandemic levels, if at all.

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The combined company’s initiatives to generate additional revenues and to reduce its costs may not be adequate or successful.

The combined company must take steps to generate additional revenues and to achieve a competitive cost structure after the merger. The adequacy and ultimate success of initiatives to generate additional revenues and/or reduce costs cannot be assured. Moreover, whether combined company’s initiatives will be adequate or successful depends in large measure on factors beyond its control. For example, the overall industry environment, including customer demand, yield and industry capacity growth, actions of competitors, the COVID-19 pandemic and fuel prices could negatively impact the success of these initiatives. It could be very difficult for the combined company to continue to fund its obligations on an ongoing basis, and to be profitable, if the overall industry revenue environment were to deteriorate or if fuel prices were to increase and persist for an extended period at high levels.

Airlines are often affected by factors beyond their control, including: air traffic congestion at airports; air traffic control inefficiencies; government shutdowns; major construction or improvements at airports; aircraft and engine defects; FAA grounding of aircraft; adverse weather conditions; increased security measures; new travel-related taxes; or the outbreak of disease, any of which could have a material adverse effect on the combined company’s business, results of operations and financial condition.

Like other airlines, the combined company’s business will be affected by factors beyond its control, including air traffic congestion at airports, air traffic control inefficiencies, government shutdowns, major construction or improvements at airports at which the combined company will operate, increased security measures, new travel-related identification requirements, taxes and fees, adverse weather conditions, natural disasters and the outbreak of disease. Flight delays caused by these factors may frustrate passengers and may increase costs and decrease revenues, which in turn could adversely affect profitability. The federal government controls all U.S. airspace, and airlines are completely dependent on the FAA to operate that airspace in a safe, efficient and affordable manner. The federal government also controls airport security. The air traffic control system, which is operated by the FAA, faces challenges in managing the growing demand for U.S. air travel. U.S. and foreign air-traffic controllers often rely on outdated technologies that routinely overwhelm the system and compel airlines to fly inefficient, indirect routes resulting in delays. In addition, federal government slowdowns or shutdowns may further impact the availability of federal resources, such as air traffic controllers and security personnel, necessary to provide air traffic control and airport security, which may cause delays or cancellations of flights or may impact the combined company’s ability to take delivery of aircraft or expand the combined company’s route network or airport footprint. Further, implementation of the Next Generation Air Transport System, or NextGen, by the FAA could result in changes to aircraft routings and flight paths that could lead to increased noise complaints and other lawsuits, resulting in increased costs. The U.S. Congress could enact legislation that could impose a wide range of consumer protection requirements, which could increase the combined company’s costs of doing business.

In addition, airlines may also experience disruptions to their operations as a result of the aircraft and engines they operate, such as manufacturing defects, spare part shortages and other factors beyond their control. For example, regulators ordered the grounding of the entire worldwide Boeing 737 MAX fleet in March 2019. While such order did not have a direct impact on Frontier’s fleet, which is comprised entirely of Airbus A320 and Airbus A321 aircraft, or on Spirit’s fleet, which is comprised entirely of Airbus A319, Airbus A320 and Airbus A321 family aircraft, any similar or other disruption to the combined company’s operations could have a material adverse effect on the combined company’s business, results of operations and financial condition.

Adverse weather conditions and natural disasters, such as hurricanes, tornadoes, thunderstorms, blizzards, snowstorms or earthquakes, can cause flight cancellations or significant delays. Cancellations or delays due to adverse weather conditions or natural disasters, air traffic control problems or inefficiencies, breaches in security or other factors may affect the combined company to a greater degree than other larger airlines that may be able to recover more quickly from these events, and therefore could have a material adverse effect on the combined

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company’s business, results of operations and financial condition to a greater degree than other air carriers. Because of the combined company’s expected high utilization and point-to-point network, operational disruptions can have a disproportionate impact on its ability to recover. In addition, many airlines re-accommodate their disrupted passengers on other airlines at prearranged rates under flight interruption manifest agreements. Frontier and Spirit have been unsuccessful in procuring any of these agreements with their peers, which will make the combined company’s recovery from disruption more challenging than for larger airlines that have these agreements in place. Similarly, outbreaks of contagious diseases, such as COVID-19, Ebola, measles, avian flu, severe acute respiratory syndrome (SARS), H1N1 (swine) flu, pertussis (whooping cough) and Zika virus, have in the past and may in the future result in significant decreases in passenger traffic and the imposition of government restrictions in service, resulting in a material adverse impact on the airline industry. New identification requirements, such as the implementation of rules under the REAL ID Act of 2005, and increased travel taxes, such as those provided in the Travel Promotion Act, enacted in March 2010, which charges visitors from certain countries a $10 fee every two years to travel into the United States to subsidize certain travel promotion efforts, could also result in decreases in passenger traffic. Any general reduction in

airline passenger traffic could have a material adverse effect on the combined company’s business, results of operations and financial condition.

The deployment of new 5G C-band service by wireless communications service providers could have a material adverse effect on the combined company’s operations, which in turn could negatively impact our business, results of operations and financial condition.

On January 17, 2022, various executives of U.S. passenger airlines and cargo carriers, and airline industry associations, warned the U.S. federal government of the potential adverse impact the imminent deployment of AT&T and Verizon’s new 5G C-band service would have on U.S. aviation operations. According to aviation leaders, the deployment of the new 5G C-band service could cause, among other consequences, operational and security issues, interference with critical aircraft instruments and adverse impact to low-visibility operations. Any of these consequences could potentially cause flight cancellations, diversions and delays, or could result in damage to our aircraft and other equipment and a diminished margin of safety in airline operations. The DOT and the FAA are currently working with AT&T and Verizon to create appropriate safeguards in the deployment of their new 5G C-band service, including a potential delay in its overall deployment, the installation of buffer zones around airports and other measures to be announced. Any requirements or restrictions imposed on airlines by the DOT, the FAA or other government agencies are uncertain, but could have an adverse effect on the combined company’s operations. Any sustained impact to the combined company’s operations could adversely affect the combined company’s business, results of operations and financial condition.

The airline industry is exceedingly competitive, and the combined company will compete against legacy network airlines, low-cost carriers and other ultra low-cost carriers; if the combined company is not able to compete successfully in its markets, its business will be materially adversely affected.

The combined company will face significant competition with respect to routes, fares and services. Within the airline industry, the combined company will compete with legacy network carriers, low cost carriers (which we refer to as “LCCs”) and other ULCCs. Competition on most of the routes Frontier and Spirit presently serve is intense, due to the large number of carriers in those markets. Furthermore, other airlines may begin service or increase existing service on routes where Frontier or Spirit currently faces no or little competition. In almost all instances, the combined company’s competitors will be larger than the company combined and possess significantly greater financial and other resources than the combined company does.

The airline industry is particularly susceptible to price discounting because, once a flight is scheduled, airlines incur only nominal additional costs to provide service to passengers occupying otherwise unsold seats. Increased fare or other price competition could adversely affect the combined company’s operations. Airlines typically use discount fares and other promotions to stimulate traffic during normally slower travel periods to generate cash flow and to increase revenue per available seat mile. The prevalence of discount fares can be particularly acute

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when a competitor has excess capacity to sell. Given the high levels of excess capacity among U.S. airlines generally as a result of the COVID-19 pandemic, the combined company will face significant discounted fare competition as the U.S. market continues to recover. Moreover, many other airlines have unbundled their services, at least in part, by charging separately for services such as baggage and advance seat selection which previously were offered as a component of base fares. This unbundling and other cost-reducing measures could enable competitor airlines to reduce fares on routes that the combined company will serve.

In addition, airlines increase or decrease capacity in markets based on perceived profitability. If the combined company’s competitors increase overall industry capacity, or capacity dedicated to a particular domestic or foreign region, market or route that the combined company will serve, it could have a material adverse impact on the combined company’s business. For instance, in 2017 there was widespread capacity growth across the United States, including in many of the markets in which the combined company will operate. In particular, during 2017, both Southwest Airlines and United Airlines increased their capacity in Denver. The domestic airline industry has often been the source of fare wars undertaken to grow market share or for other reasons, including, for example, actions by American Airlines in 2015 and United Airlines in 2017 to match fares offered in many of their markets by ULCCs, with resulting material adverse effects on the revenues of the airlines involved. The increased capacity across the United States in 2017 exacerbated the competitive pricing environment, particularly beginning in the second quarter of 2017, and this activity continued throughout 2018 and the first half of 2019. Given the decreased demand resulting from the COVID-19 pandemic, the combined company will face significant competition, including price competition, at least in the short term and as the U.S. market recovers. If the combined company experiences increased competition, its business could be materially adversely affected.

Frontier also expects that new work patterns and the growth of remote work will lead to increasing numbers of employees choosing to live remotely from their office location, which could significantly alter the historical demand levels on the routes that the combined company will serve. While Frontier believes its low fares and low costs will enable the combined company to grow its network in new markets profitably to take advantage of new demand patterns as they arise, there can be no assurance that the combined company will be successful in doing so or that it will be able to successfully compete with other U.S. airlines on such routes. If the combined company fails to establish itself in such new markets, the combined company’s business could be materially adversely affected.

The combined company’s growth and the success of its ULCC business model could stimulate competition in the airline industry through its competitors’ development of their own ULCC strategies. Additionally, several new market entrants, including Avelo Airlines and Breeze Airways, have commenced, or announced their intent to commence, operations, which could present further competition should they develop ULCC strategies. For example, certain legacy network airlines have further segmented the cabins of their aircraft in order to enable them to offer a tier of reduced base fares designed to be competitive with those offered by Frontier, Spirit and other ULCCs. Frontier expects the legacy airlines to continue to match LCC and ULCC pricing on portions of their network. A competitor adopting a ULCC strategy may have greater financial resources and access to lower cost sources of capital than the combined company will, which could enable them to execute a ULCC strategy with a lower cost structure than the combined company can. If these competitors adopt and successfully execute a ULCC business model, the combined company’s business, results of operations and financial condition could be materially adversely affected.

There has been significant consolidation within the airline industry, including, for example, the combinations of American Airlines and US Airways, Delta Air Lines and Northwest Airlines, United Airlines and Continental Airlines, Southwest Airlines and AirTran Airways, Alaska Airlines and Virgin America, and Frontier’s pending merger with Spirit. In the future, there may be additional consolidation in the airline industry. Business combinations could significantly alter industry conditions and competition within the airline industry and could enable the combined company’s competitors to reduce their fares.

The extremely competitive nature of the airline industry could prevent the combined company from attaining the level of passenger traffic or maintaining the level of fares or revenues related to non-fare services required to

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achieve and sustain profitable operations in new and existing markets and could impede the combined company’s growth strategy, which could harm its operating results. Due to the combined company’s relatively small size, it will be susceptible to a fare war or other competitive activities in one or more of the markets it serves, which could have a material adverse effect on the combined company’s business, results of operations and financial condition.

The combined company will depend on a limited number of suppliers for aircraft and engines.

A critical cost-saving element of the combined company’s anticipated business strategy will be to operate a single-family aircraft fleet; however, the combined company’s dependence on the Airbus A320 family aircraft for its aircraft and on CFM International and Pratt & Whitney for its engines will make the combined company vulnerable to any design defects, mechanical problems or other technical or regulatory issues associated with this aircraft type or these engines. In the event of any actual or suspected design defects or mechanical problems with the Airbus A320 family aircraft or CFM International or Pratt & Whitney engines, whether involving the combined company’s aircraft or that of another airline, the combined company may choose, or be required, to suspend or restrict the use of its aircraft.

The combined company’s business could also be materially adversely affected if the public avoids flying on the its aircraft due to an adverse perception of the Airbus A320 family aircraft or CFM International or Pratt & Whitney engines, whether because of safety concerns or other problems, real or perceived, or in the event of an accident involving such aircraft or engines. Separately, if any of Airbus, CFM International or Pratt & Whitney becomes unable to perform its contractual obligations and the combined company must lease or purchase aircraft or engines from another supplier, the combined company would incur substantial transition costs, including expenses related to acquiring new aircraft, engines, spare parts, maintenance facilities and training activities, and would lose the cost benefits from its current single-fleet composition, any of which would have a material adverse effect on the combined company’s business, results of operations and financial condition. These risks may be exacerbated by the long-term nature of the combined company’s fleet and order book and the unproven new engine technology to be utilized by the aircraft in the combined company’s order book.

Unauthorized use, unauthorized incursions or user exploitation of the combined company’s information technology infrastructure could compromise the personally identifiable information of its passengers, prospective passengers or personnel, and other sensitive information and expose the combined company to liability, damage its reputation and have a material adverse effect on its business, results of operations and financial condition.

In the processing of the combined company’s customer transactions and as part of the combined company’s ordinary business operations, the combined company and certain of its third-party specialists will collect, process, transmit and store a large volume of personally identifiable information of its passengers, prospective passengers or personnel, including email addresses, home addresses, financial data such as credit and debit card information and other sensitive information. The security of the systems and network where the combined company and its third-party specialists will store this data will be a critical element of the combined company’s business, and these systems and the combined company’s network may be vulnerable to cyberattacks and other security issues, including threats potentially involving criminal hackers, hacktivists, state-sponsored actors, corporate espionage, employee malfeasance and human or technological error. Threats to cybersecurity have increased with the sophistication of malicious actors, and the combined company will have to manage those evolving risks. Frontier and Spirit have been the targets of cybersecurity attacks in the past and Frontier expects the combined company will continue to be targeted in the future. Recently, several high-profile companies have experienced significant data breaches and ransom attacks, which have caused those companies to suffer substantial financial and reputational harm. Failure to appropriately address these issues could also give rise to potentially material legal risks and liabilities.

A significant cybersecurity incident could result in a range of potentially material negative consequences for the combined company, including lost revenue; unauthorized access to, disclosure, modification, misuse, loss or

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destruction of company systems or data; theft of sensitive, regulated or confidential data, such as personal identifying information or the combined company’s intellectual property; the loss of functionality of critical systems through ransomware, denial of service or other attacks; and business delays, service or system disruptions, damage to equipment and injury to persons or property. The costs and operational consequences of defending against, preparing for, responding to and remediating an incident may be substantial. As cybersecurity threats become more frequent, intense and sophisticated, costs of proactive defense measures are increasing. Further, the combined company could be exposed to litigation, regulatory enforcement or other legal action as a result of an incident, carrying the potential for damages, fines, sanctions or other penalties, as well as injunctive relief requiring costly compliance measures. A cybersecurity incident could also impact the combined company’s brand, harm its reputation and adversely impact its relationship with customers, employees and stockholders. Additionally, any material failure by the combined company or its third-party specialists to maintain compliance with the Payment Card Industry security requirements or to rectify a data security issue may result in fines and restrictions on the combined company’s ability to accept credit and debit cards as a form of payment. While Frontier and Spirit have taken precautions to avoid an unauthorized incursion of their computer systems, Frontier cannot ensure that those precautions are either adequate or implemented properly to prevent and detect a data breach or other cybersecurity incident and its adverse financial and reputational consequences to the combined company’s business.

The combined company will also be subject to increasing legislative, regulatory and customer focus on privacy issues and data security in the United States and abroad. The compromise of the combined company’s technology systems resulting in the loss, disclosure, misappropriation of or access to the personally identifiable information of its passengers, prospective passengers or personnel could result in governmental investigation, civil liability or regulatory penalties under laws protecting the privacy of personal information, any or all of which could disrupt the combined company’s operations and have a material adverse effect on its business, results of operations and financial condition. In addition, a number of the combined company’s commercial partners, including credit card companies, have imposed data security standards that will apply to the combined company, and these standards continue to evolve. The combined company will make an effort to meet its privacy and data security obligations; however, it is possible that certain new obligations may be difficult to meet and could increase the combined company’s costs.

Threatened or actual terrorist attacks or security concerns, particularly involving airlines, could have a material adverse effect on the combined company’s business, results of operations and financial condition.

Past terrorist attacks or attempted attacks, particularly those against airlines, have caused substantial revenue losses and increased security costs, and any actual or threatened terrorist attack or security breach, even if not directly against an airline, could have a material adverse effect on the combined company’s business, results of operations and financial condition. For instance, enhanced passenger screening, increased regulation governing carry-on baggage and other similar restrictions on passenger travel may further increase passenger inconvenience and reduce the demand for air travel. In addition, increased or enhanced security measures have tended to result in higher governmental fees imposed on airlines, resulting in higher operating costs for airlines, which the combined company may not be able to pass on to consumers in the form of higher prices. Terrorist attacks made directly on an airline, particularly in the U.S., or the fear of such attacks or other hostilities (including elevated national threat warnings or selective cancellation or redirection of flights due to terror threats), would have a negative impact on the airline industry and have a material adverse effect on the combined company’s business, results of operations and financial condition.

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The combined company’s inability to expand or operate reliably or efficiently out of airports where it maintains a large presence could have a material adverse effect on its business, results of operations and financial condition.

The combined company’s results of operations may be affected by actions taken by governmental or other agencies or authorities having jurisdiction over its airports, including, but not limited to:

In general, any changes in airport operations could have a material adverse effect on the combined company’s business, results of operations and financial condition.

The COVID-19 pandemic and measures to reduce its spread are expected to have, a material adverse impact on the combined company’s business, results of operations and financial condition.

COVID-19 has spread to almost every country in the world, including the United States. The World Health Organization has declared COVID-19 a pandemic. The outbreak of COVID-19 and the implementation of measures to reduce its spread have adversely impacted Frontier and Spirit’s businesses and are expected to adversely impact the combined company in a number of ways. Multiple governments in countries the combined company will serve, principally the United States, have responded to the virus with air travel restrictions, closures or recommendations against air travel, and the implementation of mandatory quarantine periods after travel, and certain countries the combined company will serve have required airlines to limit or completely stop operations. Although there has been significant recovery of demand through the year ended December 31, 2021, as compared to the year ended December 31, 2020, Frontier and Spirit are unable to predict the future spread and impact of COVID-19, including future variants of the virus such as the recent Delta and Omicron variants, nor the efficacy and adherence rates of vaccines and other therapeutics and the resulting measures that may be introduced by governments or other parties and what impact those measures may have on the demand for air travel. Frontier and Spirit are closely monitoring the impact of the Delta and Omicron variants and expects any impact to be short term in nature given the availability of vaccines and the likely increase in vaccination rates in response to these variants.

The extent of the impact of the COVID-19 pandemic on the combined company’s business, results of operations and financial condition will depend on future developments, including the currently unknowable duration of the COVID-19 pandemic; the efficacy and adherence rates of COVID-19 vaccines; impact of existing and future governmental regulations, travel advisories, testing regimes and restrictions that are imposed in response to the COVID-19 pandemic; additional reductions to the combined company’s flight capacity, or a voluntary temporary

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cessation of all flights, that the combined company implements in response to the COVID-19 pandemic; and the impact of the COVID-19 pandemic on consumer behavior, such as a reduction in the demand for air travel, especially in what will be the combined company’s destination cities. The potential economic impact brought on by the COVID-19 pandemic is difficult to assess or predict, and it has already caused, and is likely to result in further, significant disruptions of global economies and financial markets, which may reduce the combined company’s ability to access capital on favorable terms or at all, and increase the cost of capital. In addition, a recession, depression or other sustained adverse economic event, including, but not limited to, an inflationary economic environment, would materially adversely impact the combined company’s business and the value of its common stock. The COVID-19 pandemic makes it more challenging for management to estimate future performance of the combined company’s business, particularly over the near to medium term. A further significant decline in demand for the combined company’s flights could have a materially adverse impact on its business, results of operations and financial condition.

The combined company will also be dependent upon successful COVID-19 vaccines, including an efficient distribution and sufficient supply, and significant uptake by the general public in order to normalize economic conditions, the airline industry and the combined company’s business operations and to realize the combined company’s growth plans and business strategy. Frontier cannot predict if or when it will be able to resume full normal operations. The failure of a vaccine, including to the extent it is not effective against the future variants of the virus such as the most recent Delta and Omicron variants, significant unplanned adverse reactions to the vaccine, politicization of the vaccine or general public distrust of the vaccine could have an adverse effect on the combined company’s business, results of operations and financial condition. Legally required vaccine mandates have been imposed and have resulted in multiple unresolved court challenges, some of which remain ongoing. Frontier cannot predict what policies it may determine, or be required, to implement in the future, or the effect thereof on the combined company’s business, including whether the imposition of a mandatory vaccination requirement could cause the combined company to lose, or experience difficulties hiring, qualified personnel.

In addition, an outbreak of another disease or similar public health threat, or fear of such an event, that affects travel demand, travel behavior or travel restrictions could adversely impact the combined company’s business, results of operations and financial condition. Outbreaks of other diseases could also result in increased government restrictions and regulation, such as those actions described above or otherwise, which could adversely affect the combined company’s operations.

The COVID-19 pandemic may also exacerbate other risks described in this “Risk Factors” section, including, but not limited to, the combined company’s competitiveness, demand for its services, shifting consumer preferences and the combined company’s substantial amount of outstanding indebtedness.

The combined company’s reputation and business could be adversely affected in the event of an emergency, accident or similar public incident involving its aircraft or personnel.

The combined company will be exposed to potential significant losses and adverse publicity in the event that any of its aircraft or personnel is involved in an emergency, accident, terrorist incident or other similar public incident, which could expose the combined company to significant reputational harm and potential legal liability. In addition, the combined company could face significant costs or lost revenues related to repairs or replacement of a damaged aircraft and its temporary or permanent loss from service. Frontier cannot ensure that the combined company will not be affected by such events or that the amount of the combined company’s insurance coverage will be adequate in the event such circumstances arise, and any such event could cause a substantial increase in the combined company’s insurance premiums. In addition, any future emergency, accident or similar incident involving the combined company’s aircraft or personnel, even if fully covered by insurance or even if it does not involve the combined company’s airline, may create an adverse public perception about the combined company’s airline or that the equipment it flies is less safe or reliable than other transportation alternatives, or, in the case of the combined company’s aircraft, could cause the combined company to perform time-consuming and costly inspections on its aircraft or engines, any of which could have a material adverse effect on the combined company’s business, results of operations and financial condition.

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The airline industry is heavily taxed.

The airline industry is subject to extensive government fees and taxation that will negatively impact the combined company’s revenue. The U.S. airline industry is one of the most heavily taxed of all industries. These fees and taxes have grown significantly for domestic flights, and various U.S. fees and taxes also are assessed on international flights. For example, as permitted by federal legislation, most major U.S. airports impose a passenger facility charge per passenger on Frontier and Spirit airplanes. In addition, the combined company will be obligated to collect a federal excise tax, commonly referred to as the “ticket tax,” on domestic and international air transportation. The combined company will collect the excise tax, along with certain other U.S. and foreign taxes and user fees on air transportation (such as a per-ticket tax on passengers to fund the Transportation Security Administration (which we refer to as “TSA”)), and pass along the collected amounts to the appropriate governmental agencies. Although these taxes are not operating expenses, they represent an additional cost to the combined company’s customers. There are continuing efforts in Congress and in other countries to raise different portions of the various taxes, fees and charges imposed on airlines and their passengers. Increases in such taxes, fees and charges could negatively impact the combined company’s business, results of operations and financial condition. Under DOT regulations, all governmental taxes and fees must be included in the fares that the combined company quotes or advertises to its customers. Due to the competitive revenue environment, many increases in these fees and taxes have been absorbed by the airline industry rather than being passed on to the customer. Further increases in fees and taxes may reduce demand for air travel, and thus the combined company’s revenues.

The need to integrate the Frontier and Spirit workforces following the merger and negotiate new joint labor agreements presents the potential for delay in achieving expected synergies, increased labor costs or labor disputes that could adversely affect the combined company’s operations.

The successful integration of Frontier and Spirit and achievement of the anticipated benefits of the merger depend significantly on integrating Frontier and Spirit’s employee groups and on maintaining productive employee relations. Failure to do so presents the potential for delays in achieving expected synergies of integration, increased labor costs and labor disputes that could adversely affect the combined company’s operations.

Frontier and Spirit are both highly unionized companies. The process for integrating labor groups in an airline merger is governed by a combination of the Railway Labor Act (which we refer to as the “RLA”), the McCaskill-Bond Act, and where applicable, the existing provisions of each company’s collective bargaining agreements and union policy. Pending operational integration, it is generally necessary to maintain a “fence” between employee groups, during which time the combined company will keep the employee groups separate and apply the terms of the existing collective bargaining agreements unless other terms have been negotiated.

Under the RLA, the National Mediation Board (which we refer to as the “NMB”) has exclusive authority to resolve representation disputes arising out of airline mergers. The disputes that the NMB has authority to resolve include (i) whether the merger has created a “single carrier” for representation purposes; (ii) designation of the appropriate “craft or class”—the RLA term for “bargaining unit”—for bargaining at the combined company on a system wide basis, an issue which typically arises from minor inconsistencies over which positions are included within a particular craft or class at the two companies; and (iii) designation of the representative of each craft or class at the combined company.

In order to fully integrate the pre-merger represented employee groups, the combined company must negotiate a joint collective bargaining agreement covering each combined group. These negotiations can begin immediately where the same union represents employees of both companies within the craft or class in question, but otherwise will likely begin after a single post-merger representative has been certified by the NMB.

Prior to the completion of the merger, there is a risk of litigation or arbitration by unions or individual employees that could delay or halt the merger or result in monetary damages on the basis that the merger either violates a

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provision of an existing collective bargaining agreement or an obligation under the RLA or other applicable law. The unions or individual employees might also pursue judicial or arbitral claims arising out of changes implemented as a result of the merger. There is also a possibility that employees or unions could engage in job actions such as slow-downs, work-to-rule campaigns, sick-outs or other actions designed to disrupt Frontier and Spirit’s normal operations, whether in opposition to the merger or in an attempt to pressure the companies in collective bargaining negotiations. Although the RLA makes such actions unlawful until the parties have been lawfully released to self-help, and Frontier and Spirit can seek injunctive relief against premature self-help, such actions can cause significant harm even if ultimately enjoined.

The combined company will be subject to extensive regulation by the Federal Aviation Administration, the Department of Transportation, Transportation Security Administration, U.S. Customs and Border Protection and other U.S. and foreign governmental agencies, compliance with which could cause increased costs and adversely affect the combined company’s business, results of operations and financial condition.

Airlines are subject to extensive regulatory and legal compliance requirements, both domestically and internationally, that involve significant costs. In the last several years, Congress has passed laws and the FAA, DOT and TSA have issued regulations, orders, rulings and guidance relating to the operation, safety, and security of airlines and consumer protections that have required significant expenditures. The combined company will incur expenses in connection with complying with such laws and government regulations, orders, rulings and guidance. Additional laws, regulations, taxes and increased airport rates and charges have been proposed from time to time that could significantly increase the cost of airline operations or reduce the demand for air travel. If adopted, these measures could have the effect of raising ticket prices, reducing revenue, and increasing costs.

For example, the DOT has broad authority over airlines and their consumer and competitive practices, and has used this authority to issue numerous regulations and pursue enforcement actions, including rules and fines relating to the handling of lengthy tarmac delays, consumer notice and disclosure requirements, consumer complaints, price and airline advertising, oversales and involuntary denied boarding process and compensation, ticket refunds, liability for loss, delay or damage to baggage, customer service commitments, contracts of carriage and the transportation of passengers with disabilities. Among these is the series of Enhanced Airline Passenger Protection rules issued by the DOT. In addition, the FAA Reauthorization Act of 2018, signed into law on October 5, 2018, provided for several new requirements and rulemakings related to airlines, including but not limited to: (i) prohibition on voice communication cell phone use during certain flights, (ii) insecticide use disclosures, (iii) new training policy best practices for training regarding racial, ethnic, and religious non-discrimination, (iv) training on human trafficking for certain staff, (v) departure gate stroller check-in, (vi) the protection of pets on airplanes and service animal standards, (vii) requirements to refund promptly to passengers any ancillary fees paid for services not received, (viii) consumer complaint process improvements, (ix) pregnant passenger assistance, (x) restrictions on the ability to deny a revenue passenger permission to board or involuntarily remove such passenger from the aircraft, (xi) minimum customer service standards for large ticket agents, (xii) information publishing requirements for widespread disruptions and passenger rights, (xiii) submission of plans pertaining to employee and contractor training consistent with the Airline Passengers with Disabilities Bill of Rights, (xiv) ensuring assistance for passengers with disabilities, (xv) flight attendant duty period limitations and rest requirements, including submission of a fatigue risk management plan, (xvi) submission of policy concerning passenger sexual misconduct, (xvii) development of Employee Assault Prevention and Response Plan related to the customer service agents, (xviii) increased penalties available related to harm to passengers with disabilities or damage to wheelchairs or mobility aids and (xix) minimum dimensions for passenger seats.

Furthermore, in 2019, the FAA published an Advance Notice of Proposed Rulemaking regarding flight attendant duty period limitations and rest requirements. The DOT also published a Notice of Proposed Rulemaking in January 2020 regarding, for example, the accessibility features of lavatories and onboard wheelchair requirements on certain single-aisle aircraft with an FAA certificated maximum capacity of 125 seats or more, training flight attendants to proficiency on an annual basis to provide assistance in transporting qualified

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individuals with disabilities to and from the lavatory from the aircraft seat, and providing certain information on request to qualified individuals with a disability or persons inquiring on their behalf, on the carrier’s website, and in printed or electronic form on the aircraft concerning the accessibility of aircraft lavatories. The DOT also recently published Final Rules regarding traveling by air with service animals and defining unfair or deceptive practices. The DOT also recently published a Final Rule clarifying that the maximum amount of denied boarding compensation that a carrier may provide to a passenger denied boarding involuntarily is not limited, prohibiting airlines from involuntarily denying boarding to a passenger after the passenger’s boarding pass has been collected or scanned and the passenger has boarded (subject to safety and security exceptions), raising the liability limits for denied boarding compensation and raising the liability limit for mishandled baggage in domestic air transportation. In addition, the FAA issued its final regulations governing pilot rest periods and work hours for all passenger airlines certificated under Part 121 of the Federal Aviation Regulations (which we refer to as “FAR”). The rule known as FAR Part 117, which became effective January 4, 2014, impacts the required amount and timing of rest periods for pilots between work assignments and modifies duty and rest requirements based on the time of day, number of scheduled segments, time zones and other factors. In addition, Congress enacted a law and the FAA issued regulations requiring U.S. airline pilots to have a minimum number of hours as a pilot in order to qualify for an Air Transport Pilot certificate, which all pilots on U.S. airlines must obtain. Compliance with these rules may increase the combined company’s costs, while failure to remain in full compliance with these rules may subject the combined company to fines or other enforcement action. FAR Part 117 and the minimum pilot hour requirements may also reduce the combined company’s ability to meet flight crew staffing requirements. Frontier and Spirit cannot assure that compliance with these and other laws, regulations, orders, rulings and guidance will not have a material adverse effect on the combined company’s business, results of operations and financial condition.

In addition, the TSA mandates the federalization of certain airport security procedures and imposes additional security requirements on airports and airlines, some of which is funded by a security fee imposed on passengers and collected by airlines. Frontier and Spirit cannot forecast what additional security and safety requirements may be imposed in the future or the costs or revenue impact that would be associated with complying with such requirements.

The combined company’s ability to operate as an airline will be dependent on its obtaining and maintaining authorizations issued to the combined company by the DOT and the FAA. The FAA from time to time issues directives and other mandatory orders relating to, among other things, operating aircraft, the grounding of aircraft, maintenance and inspection of aircraft, installation of new safety-related items and removal and replacement of aircraft parts that have failed or may fail in the future. These requirements can be issued with little or no notice, can impact the combined company’s ability to efficiently or fully utilize its aircraft, and could result in the temporary grounding of aircraft types altogether. A decision by the FAA to ground, or require time-consuming inspections of or maintenance on, the combined company’s aircraft, for any reason, could negatively affect its business, results of operations and financial condition. Federal law requires that air carriers operating scheduled service be continuously “fit, willing and able” to provide the services for which they are licensed. The combined company’s “fitness” will be monitored by the DOT, which considers managerial competence, operations, finances and compliance record. In addition, under federal law, the combined company must be a U.S. citizen (as determined under applicable law). While the DOT has seldom revoked a carrier’s certification for lack of fitness, such an occurrence would render it impossible for the combined company to continue operating as an airline. The DOT may also institute investigations or administrative proceedings against airlines for violations of regulations.

International routes are regulated by air transport agreements and related agreements between the United States and foreign governments. The combined company’s ability to operate international routes is subject to change, as the applicable agreements between the United States and foreign governments may be amended from time to time. The combined company’s access to new international markets may be limited by the applicable air transport agreements between the U.S. and foreign governments and the combined company’s ability to obtain the necessary authority from the U.S. and foreign governments to fly the international routes. In addition, the

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combined company’s operations in foreign countries are subject to regulation by foreign governments and the combined company’s business may be affected by changes in law and future actions taken by such governments, including granting or withdrawal of government approvals, airport slots and restrictions on competitive practices. The combined company will be subject to numerous foreign regulations in the countries outside the United States where it will provide service. If the combined company is not able to comply with this complex regulatory regime, its business could be significantly harmed.

Changes in legislation, regulation and government policy may have a material adverse effect on the combined company’s business.

Changes in, and uncertainty with respect to, legislation, regulation and government policy at the local, state or federal level may significantly impact the combined company’s business and the airline industry as a whole. Specific legislative and regulatory proposals that could have a material impact on the combined company in the future include, but are not limited to, infrastructure renewal programs; changes to operating and maintenance requirements and immigration and security policy and requirements; modifications to international trade policy, including withdrawing from trade agreements and imposing tariffs; changes to consumer protection laws; public company reporting requirements; environmental regulation; tax legislation and antitrust enforcement. Any such changes may make it more difficult and/or more expensive for the combined company to obtain new aircraft or engines and parts to maintain existing aircraft or engines or make it less profitable or prevent the combined company from flying to or from some of the destinations we currently serve. To the extent that any such changes have a negative impact on the combined company or the airline industry in general, including as a result of related uncertainty, these changes may materially impact the combined company’s business, results of operations, financial condition and cash flows.

Other Risk Factors of Frontier and Spirit

Frontier and Spirit’s businesses are and will be subject to the risks described above. In addition, Frontier and Spirit are, and will continue to be, and the combined company after the merger will be, subject to the risks described in Frontier and Spirit’s Annual Reports, as updated by subsequent Quarterly Reports on Form 10-Q, all of which are filed with the SEC and incorporated by reference into this information statement and proxy statement/prospectus. Please see “Where You Can Find More Information” beginning on page 204 of this information statement and proxy statement/prospectus for the location of information incorporated by reference into this information statement and proxy statement/prospectus.

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CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS

Certain statements in this information statement and proxy statement/prospectus, including statements concerning Frontier, Spirit, the proposed transactions and other matters, should be considered forward-looking within the meaning of the Securities Act of 1933, as amended, the Securities Exchange Act of 1934, as amended, and the Private Securities Litigation Reform Act of 1995. These forward-looking statements are based on Frontier’s and Spirit’s current expectations and beliefs with respect to certain current and future events and anticipated financial and operating performance. Such forward-looking statements are and will be subject to many risks and uncertainties relating to Frontier’s and Spirit’s operations and business environment that may cause actual results to differ materially from any future results expressed or implied in such forward looking statements. Words such as “expects,” “will,” “plans,” “intends,” “anticipates,” “indicates,” “remains,” “believes,” “estimates,” “forecast,” “guidance,” “outlook,” “goals,” “targets” and other similar expressions are intended to identify forward-looking statements. Additionally, forward-looking statements include statements that do not relate solely to historical facts, such as statements which identify uncertainties or trends, discuss the possible future effects of current known trends or uncertainties, or which indicate that the future effects of known trends or uncertainties cannot be predicted, guaranteed, or assured. All forward-looking statements in this information statement and proxy statement/prospectus are based upon information available to Frontier and Spirit on the date of this information statement and proxy statement/prospectus. Frontier and Spirit undertake no obligation to publicly update or revise any forward-looking statement, whether as a result of new information, future events, changed circumstances, or otherwise, except as required by applicable law. All written and oral forward-looking statements concerning the merger or other matters addressed in this information statement and proxy statement/prospectus and attributable to Frontier, Spirit, or any person acting on their behalf are expressly qualified in their entirety by the cautionary statements contained or referred to in this information statement and proxy statement/prospectus.

Actual results could differ materially from these forward-looking statements due to numerous factors including, without limitation, the following: the occurrence of any event, change or other circumstances that could give rise to the right of one or both of the parties to terminate the merger agreement; failure to obtain applicable regulatory or Spirit stockholder approval in a timely manner or otherwise; failure to satisfy other closing conditions to the proposed transactions; failure of the parties to consummate the transaction; risks that the new businesses will not be integrated successfully or that the combined company will not realize estimated cost savings, value of certain tax assets, synergies and growth, or that such benefits may take longer to realize than expected; failure to realize anticipated benefits of the combined operations; risks relating to unanticipated costs of integration; demand for the combined company’s services; the growth, change and competitive landscape of the markets in which the combined company participates; expected seasonality trends; diversion of managements’ attention from ongoing business operations and opportunities; potential adverse reactions or changes to business or employee relationships, including those resulting from the announcement or completion of the transaction; risks related to investor and rating agency perceptions of each of the parties and their respective business, operations, financial condition and the industry in which they operate; risks related to the potential impact of general economic, political and market factors on the companies or the proposed transaction; that Frontier’s cash and cash equivalents balances, together with the availability under certain credit facilities made available to Frontier and certain of its subsidiaries under its existing credit agreements, will be sufficient to fund Frontier’s operations including capital expenditures over the next 12 months; Frontier’s expectation that based on the information presently known to management, the potential liability related to Frontier’s current litigation will not have a material adverse effect on its financial condition, cash flows or results of operations; that the COVID-19 pandemic will continue to impact the businesses of the companies; ongoing and increase in costs related to IT network security; and other risks and uncertainties discussed in the section entitled “Risk Factors” beginning on page 24 and as set forth from time to time under the sections captioned “Risk Factors” in Frontier’s and Spirit’s reports and other documents filed with the SEC from time to time, including their Annual Reports on Form 10-K and Quarterly Reports on Form 10-Q.

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THE SPIRIT SPECIAL MEETING

Date, Time and Place of Meeting

The Spirit special meeting will be held virtually via live webcast on the Internet at www.virtualshareholdermeeting.com/SAVE2022SM, on June 10, 2022, at 9:00 a.m. Eastern Time.

Matters to Be Considered

At the Spirit special meeting, Spirit stockholders will be asked to consider and vote upon the following matters:

Recommendation of the Spirit Board of Directors

The Spirit board of directors has determined that the merger is advisable and in the best interests of Spirit and its stockholders and has unanimously adopted the merger agreement. The Spirit board of directors unanimously recommends that Spirit stockholders vote “FOR” the merger proposal, “FOR” the compensation proposal, and “FOR” the adjournment proposal. See “The Merger—Spirit’s Reasons for the Merger; Recommendation of the Spirit Board of Directors” for a more detailed discussion of the Spirit board of directors’ recommendation.

Spirit Record Date and Quorum

The Spirit board of directors has fixed the close of business on May 6, 2022 as the record date for determining the holders of Spirit common stock entitled to receive notice of and to vote at the Spirit special meeting.

As of the Spirit record date, there were 108,618,703 shares of Spirit common stock outstanding and entitled to vote at the Spirit special meeting held by approximately 69 holders of record. Each share of Spirit common stock entitles the holder to one vote at the Spirit special meeting on each proposal to be considered at the Spirit special meeting.

The presence at the Spirit special meeting, in person (via the Internet) or by proxy, of holders of a majority in voting power of the Spirit common stock issued and outstanding and entitled to vote at the Spirit special meeting will constitute a quorum for the transaction of business. All shares of Spirit common stock present in person (via the Internet) or represented by proxy, including abstentions, will be treated as present for purposes of determining the presence or absence of a quorum for all matters voted on at the Spirit special meeting.

Votes Required; Treatment of Abstentions and Failure to Vote

Merger proposal:

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Compensation proposal:

Adjournment proposal:

Shares Held by Officers and Directors

As of the Spirit record date, the directors and executive officers of Spirit and their affiliates beneficially owned and were entitled to vote approximately 468,079 shares of Spirit common stock representing approximately 0.431% of the shares of Spirit common stock outstanding on that date. It is expected that Spirit’s directors and executive officers will vote their shares “FOR” the merger proposal, “FOR” the compensation proposal and “FOR” the adjournment proposal. As of the Spirit record date, Frontier, the directors and officers of Frontier and their affiliates beneficially owned no shares of Spirit common stock outstanding on that date.

Voting of Proxies; Incomplete Proxies

Each copy of this information statement and proxy statement/prospectus mailed to Spirit stockholders is accompanied by a form of proxy card with instructions for voting. If you hold shares in your name as a stockholder of record, you should complete and return the proxy card accompanying this information statement and proxy statement/prospectus, regardless of whether you plan to attend (via the Internet) the Spirit special meeting.

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The procedures for voting are as follows:

Stockholder of Record: Shares Registered in Your Name

If you are a stockholder of record, you may vote at the Spirit special meeting. Alternatively, you may vote by proxy by signing, dating and returning the proxy card, over the Internet or by telephone. Whether or not you plan to attend (via the Internet) the Spirit special meeting, we urge you to vote by proxy to ensure your vote is counted. Even if you have submitted a proxy before the Spirit special meeting, you may still attend the Spirit special meeting and vote via the Internet. In such case, your previously submitted proxy will be disregarded.

Beneficial Owner: Shares Registered in the Name of Broker, Bank or Other Agent

If you are a beneficial owner of shares registered in the name of your broker, bank or other agent, you should have received a voting instruction card and voting instructions with these proxy materials from that organization rather than from us. Simply complete and mail the voting instruction card to ensure that your vote is counted. To vote (via the Internet) at the Spirit special meeting, you must obtain a valid proxy from your broker, bank or other agent. Follow the instructions from your broker, bank or other agent included with these proxy materials, or contact your broker, bank or other agent to request a proxy form.

All shares represented by valid proxies that Spirit receives through this solicitation, and that are not revoked, will be voted in accordance with your instructions on the proxy card. If you make no specification on your proxy card as to how you want your shares voted before signing and returning it, your proxy will be voted “FOR” the merger proposal, “FOR” the compensation proposal, and “FOR” the adjournment proposal. No matters other than the matters described in this information statement and proxy statement/prospectus are anticipated to be presented for action at the special meeting or at any adjournment or postponement of the Spirit special meeting. However, if other business properly comes before the Spirit special meeting, the proxy agents will, in their discretion, vote upon such matters in their best judgment.

Shares Held in “Street Name”; Broker Non-Votes

Under stock exchange rules, banks, brokers and other nominees who hold shares of Spirit common stock in “street name” for a beneficial owner of those shares typically have the authority to vote in their discretion on “routine” proposals when they have not received instructions from beneficial owners. However, banks, brokers and other nominees are not allowed to exercise their voting discretion with respect to the approval of matters determined to be “non-routine,” without specific instructions from the beneficial owner. Broker non-votes are shares held by a broker, bank or other nominee that are represented at the Spirit special meeting, but with respect to which the broker or nominee is not instructed by the beneficial owner of such shares to vote on the particular proposal and the broker does not have discretionary voting power on such proposal. If your broker, bank or other nominee holds your shares of Spirit common stock in “street name,” your broker, bank, or other nominee will vote your shares of Spirit common stock only if you provide instructions on how to vote by filling out the voter instruction form sent to you by your broker, bank or other nominee with this information statement and proxy statement/prospectus.

Revocability of Proxies and Changes to a Spirit Stockholder’s Vote

If you hold your shares of Spirit common stock in your name as a stockholder of record, you may revoke any proxy at any time before it is voted by (1) submitting another properly completed proxy over the Internet, by telephone or by mail with a later date, (2) delivering a written revocation letter to Spirit’s Secretary, or (3) attending (via the Internet) the Spirit special meeting and voting online.

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Any stockholder entitled to vote in person at the Spirit special meeting may vote online regardless of whether a proxy has been previously given, but the mere presence (without notifying Spirit’s secretary) of a stockholder at the Spirit special meeting will not by itself constitute revocation of a previously given proxy.

Written notices of revocation and other communications about revoking your proxy card should be addressed to:

Spirit Airlines, Inc.

2800 Executive Way

Miramar, Florida 33025

Attention: Secretary

If your shares of Spirit common stock are held in “street name” by a bank or broker, you should follow the instructions of your bank or broker regarding the revocation of proxies.

Solicitation of Proxies

Spirit is soliciting your proxy in conjunction with the merger. Spirit will bear the cost of soliciting proxies from you. In addition to solicitation of proxies by mail, Spirit will request that banks, brokers and other record holders send proxies and proxy material to the beneficial owners of Spirit common stock and secure their voting instructions. Spirit has also made arrangements with Okapi Partners LLC to assist it in soliciting proxies and has agreed to pay Okapi Partners LLC approximately $25,000 plus reasonable expenses for these services.

Householding of Proxy Materials

The SEC has adopted rules that permit companies and intermediaries (e.g., brokers) to satisfy the delivery requirements for proxy materials, including annual reports, with respect to two or more stockholders sharing the same address by delivering a single copy of the documents addressed to those stockholders. This process, which is commonly referred to as “householding,” potentially means extra convenience for stockholders and cost savings for companies. In accordance with these rules, only one set of documents will be delivered to multiple stockholders sharing an address unless Spirit has received contrary instructions from one or more of the stockholders.

If, at any time, you no longer wish to participate in “householding” and would prefer to receive separate copies of the proxy materials, including annual reports, please notify your broker, direct your written request to Thomas Canfield, Secretary, Spirit Airlines, Inc., 2800 Executive Way, Miramar, Florida 33025 or contact Thomas Canfield at (954) 447-7920. Stockholders who currently receive multiple copies of such documents and would like to request “householding” of their communications should contact their brokers.

Attending the Spirit Special Meeting (via the Internet)

All holders of Spirit common stock, including holders of record and stockholders who hold their shares through banks, brokers, nominees or any other holder of record, are invited to attend the Spirit special meeting (via the Internet). Stockholders of record can vote electronically at the special meeting. If you are not a stockholder of record, you must obtain a proxy executed in your favor from the record holder of your shares, such as a broker, bank or other nominee, to be able to vote electronically at the special meeting.

Assistance

If you have any questions concerning the merger or this information statement and proxy statement/prospectus, would like additional copies of this information statement and proxy statement/prospectus, or need help voting your shares of Spirit common stock, please direct your inquiry to Secretary, Spirit Airlines, Inc., 2800 Executive Way, Miramar, Florida 33025, (954) 447-7920, or Spirit’s proxy solicitor, Okapi Partners LLC, toll-free at (855) 208-8903 or via email at info@okapipartners.com.

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SPIRIT PROPOSALS

Proposal No. 1 — Merger Proposal

At the Spirit special meeting, the Spirit stockholders will be asked to adopt the merger agreement. Holders of Spirit common stock should read this information statement and proxy statement/prospectus carefully and in its entirety, including the annexes, for more detailed information concerning the merger agreement and the merger. A copy of the merger agreement is attached to this information statement and proxy statement/prospectus as Annex A.

After careful consideration, the Spirit board of directors unanimously adopted the merger agreement, authorized and approved the merger and the transactions contemplated by the merger agreement and determined the merger agreement and the merger to be advisable and in the best interests of Spirit and its stockholders. Please see “The Merger— Spirit’s Reasons for the Merger; Recommendation of the Spirit Board of Directors” included elsewhere in this information statement and proxy statement/prospectus for a more detailed discussion of the Spirit board of directors’ recommendation.

The Spirit board of directors unanimously recommends that Spirit stockholders vote “FOR” the proposal to adopt the merger agreement.

Proposal No. 2 — Compensation Proposal

Section 14A of the Exchange Act, and Rule 14a-21(c) under the Exchange Act require that Spirit seek a nonbinding advisory vote from its stockholders to approve the “golden parachute” compensation that may be paid or become payable to Spirit’s named executive officers that is based on or otherwise relates to the merger, as disclosed in “The Merger—Interests of Spirit’s Directors and Executive Officers in the Merger” beginning on page 114, including the table titled “Merger-Related Compensation for Spirit’s Named Executive Officers” and its accompanying footnotes. As required by these provisions, Spirit is asking the Spirit stockholders to cast an advisory vote on the adoption of the following resolution:

“RESOLVED, that the compensation that may be paid or become payable to Spirit’s named executive officers that is based on or otherwise relates to the merger, and the agreements or understandings pursuant to which such compensation may be paid or become payable, in each case, as disclosed pursuant to Item 402(t) of Regulation S-K in “The Merger—Interests of Spirit’s Directors and Executive Officers in the Merger” and “The Merger—Merger-Related Compensation for Spirit’s Named Executive Officers” beginning on pages 114 and 122, are hereby APPROVED on a non-binding, advisory basis.”

The vote with respect to this proposal is an advisory vote and will not be binding on Spirit, Spirit’s board of directors, Frontier, any of Spirit or Frontier’s subsidiaries or the combined company. Therefore, regardless of whether Spirit stockholders approve this proposal, if the merger agreement is approved by the stockholders and completed, the compensation that is based on or otherwise related to the merger will still be paid to Spirit’s named executive officers to the extent payable in accordance with the terms of their compensation agreements and arrangements. Approval of this compensation proposal is not a condition to the closing of the merger.

The Spirit board of directors unanimously recommends that Spirit stockholders vote “FOR” approval of the compensation proposal.

Proposal No. 3 — Adjournment Proposal

The Spirit special meeting may be adjourned to another time or place, if necessary or appropriate, to permit, among other things, further solicitation of proxies if necessary to obtain additional votes in favor of the merger proposal.

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If, at the Spirit special meeting, (i) there are insufficient shares of Spirit common stock represented (either in person or by proxy) to constitute a quorum necessary to conduct the business of such meeting, (ii) additional time is required for the filing and mailing of any supplemental or amended disclosure which Spirit has determined is reasonably likely to be required under applicable law and for such supplemental or amended disclosure to be disseminated and reviewed by Spirit stockholders prior to the meeting of Spirit stockholders, (iii) to allow reasonable additional time to solicit additional proxies, if and to the extent Spirit reasonably believes the number of shares of Spirit common stock present or represented and voting in favor of the merger proposal is insufficient to approve such proposal or (iv) if required by law, Spirit intends to move to adjourn the Spirit special meeting. In accordance with the Spirit bylaws, a vote to approve the proposal to adjourn the Spirit special meeting, if necessary or appropriate, to solicit additional proxies if there are insufficient votes at the time of the Spirit special meeting to adopt the merger proposal may be taken in the absence of a quorum.

The Spirit board of directors unanimously recommends that Spirit stockholders vote “FOR” the adjournment proposal.

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INFORMATION ABOUT THE COMPANIES

Frontier

Frontier Group Holdings, Inc.

4545 Airport Way

Denver, CO 80239

(720) 374-4550

Frontier Group Holdings, Inc. is a Delaware corporation headquartered in Denver, Colorado, and is the parent company of Frontier Airlines, Inc.

Frontier Airlines is an ultra low-cost carrier whose business strategy is focused on Low Fares Done Right^®. Frontier offers flights throughout the United States and to select near international destinations in the Americas. Frontier’s unique strategy is underpinned by our low-cost structure and superior low-fare brand. Frontier operates more than 100 A320 family aircraft and has the largest A320neo fleet in the U.S. The use of these aircraft, Frontier’s seating configuration, weight-saving tactics and baggage process have all contributed to airline’s average fuel savings compared to other U.S. airlines (fuel savings is based on Frontier Airlines’ 2019 ASMs per fuel gallon consumed compared to the weighted average of major U.S. airlines), which makes Frontier the most fuel-efficient U.S. airline. With over 230 new Airbus planes on order, Frontier will continue to grow to deliver on its mission of providing affordable travel across America.

Frontier common stock is traded on NASDAQ under the symbol “ULCC.”

Additional information about Frontier and its subsidiaries is included in documents incorporated by reference in

this information statement and proxy statement/prospectus. Please see “Where You Can Find More Information.”

Spirit

Spirit Airlines, Inc.

2800 Executive Way

Miramar, FL 33025

(954) 447-7920

Spirit was founded in 1964 as Clippert Trucking Company, a Michigan corporation. It began air charter operations in 1990 and renamed itself Spirit Airlines, Inc. in 1992. In 1994, Spirit reincorporated in Delaware, and in 1999 it relocated its headquarters to Miramar, Florida.

Spirit offers affordable travel to value-conscious customers. Its all-Airbus fleet is one of the youngest and most fuel efficient in the United States. Spirit serves 85 destinations in 16 countries throughout the United States, Latin America and the Caribbean.

Spirit’s ultra low-cost carrier, or ULCC, business model allows it to compete principally by offering customers unbundled base fares that remove components traditionally included in the price of an airline ticket. By offering customers unbundled base fares, Spirit gives customers the power to save by paying only for the Á La Smarte^TM options they choose, such as checked and carry-on bags, advance seat assignments, priority boarding and refreshments. Spirit records revenue related to these options as non-fare passenger revenue, which is recorded within passenger revenues in its consolidated statements of operations.

Spirit’s common stock trades under the symbol “SAVE” on the NYSE.

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Additional information about Spirit and its subsidiaries is included in documents incorporated by reference in this information statement and proxy statement/prospectus. Please see “Where You Can Find More Information.”

Top Gun Acquisition Corp.

Top Gun Acquisition Corp.

c/o Frontier Group Holdings, Inc.

4545 Airport Way

Denver, CO 80239

(720) 374-4550

Top Gun Acquisition Corp., a Delaware corporation, is a wholly owned subsidiary of Frontier. Merger Sub is newly formed, and was organized for the purpose of entering into the merger agreement and effecting the merger. Merger Sub has engaged in no business activities to date and it has no material assets or liabilities of any kind, other than those incident to its formation and those incurred in connection with the merger.

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THE DESCRIPTION OF FRONTIER WRITTEN CONSENT

ENTERED INTO BY FRONTIER’S MAJOR STOCKHOLDER

The Frontier stock issuance requires the affirmative consent of the holders of a majority of the outstanding Frontier common stock entitled to vote thereon.

Concurrently with the execution of the merger agreement, Indigo Fund, the holder of 178,834,034 shares of Frontier common stock, or approximately 82.4% of the shares of Frontier common stock outstanding and entitled to vote on such matters as of February 5, 2022, executed a written consent in lieu of a meeting, approving the Frontier stock issuance. As a result, no further action by any Frontier stockholder is required in connection with the approval by Frontier stockholders of the Frontier stock issuance, which is the only Frontier stockholder approval required in connection with the merger.

Because less than all of the Frontier’s stockholders approved the Frontier stock issuance, this information statement and proxy statement/prospectus serves as your notice pursuant to 228(e) of the DGCL that such corporate actions were taken. This information statement and proxy statement/prospectus shall constitute notice, pursuant to Section 228(e) of the DGCL to Frontier’s stockholders who have not consented in writing to the actions set forth in the Frontier written consent and who, if the actions had been taken at a meeting, would have been entitled to notice of the meeting if the record date for notice of such meeting had been February 5, 2022, the date the Frontier written consent was delivered to Frontier.

Frontier has not solicited and will not be soliciting its stockholders’ authorization or approval of the merger agreement, the merger or any of the other transactions contemplated by the merger agreement, including the Frontier stock issuance.

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THE MERGER

The following discussion contains certain information about the merger. The discussion is subject, and qualified in its entirety by reference, to the merger agreement attached as Annex A to this information statement and proxy statement/prospectus and incorporated herein by reference. We urge you to read carefully this entire information statement and proxy statement/prospectus, including the merger agreement attached as Annex A, for a more complete understanding of the merger.

Terms of the Merger

The Spirit board of directors and the Frontier board of directors have each unanimously approved the merger agreement. Under the merger agreement, Merger Sub will merge with and into Spirit, with Spirit continuing as the surviving corporation and a wholly owned subsidiary of Frontier, in a transaction we refer to as the merger.

Upon completion of the merger, for each share of Spirit common stock held immediately prior to the merger (except for treasury stock or shares owned by Frontier). Spirit stockholders will receive (i) $2.13 in cash, without interest, and (ii) 1.9126 shares of Frontier common stock, plus cash in lieu of fractional shares. As a result of the foregoing, based on the fully diluted number of shares of Frontier common stock and Spirit common stock as of February 4, 2022, the last trading day before public announcement of the merger, it is expected that Frontier stockholders will hold approximately 51.5%, and Spirit stockholders will hold approximately 48.5%, of the fully diluted shares of the combined company immediately after the merger.

Immediately following the execution of the merger agreement, Indigo Fund, the holder of 178,834,034 shares of Frontier common stock, or approximately 82.4% of the shares of Frontier common stock outstanding and entitled to vote on such matters as of February 4, 2022, executed a written consent in lieu of a meeting approving the Frontier stock issuance. As a result, no further action by any Frontier stockholder is required in connection with the approval by Frontier stockholders of the Frontier stock issuance, which is the only Frontier stockholder approval required in connection with the merger.

Spirit stockholders are being asked to adopt the merger agreement. See “The Merger Agreement” for additional and more detailed information regarding the legal documents that govern the merger, including information about conditions to the completion of the merger and provisions for terminating or amending the merger agreement.

Background of the Merger

Spirit’s board of directors and senior management regularly review and assess Spirit’s financial performance, prospects, competitive position and long-term strategic plan with the goal of maximizing stockholder value. As part of this ongoing process, the Spirit board of directors and senior management have periodically evaluated potential strategic alternatives relating to Spirit and its business and have engaged in discussions with third parties concerning potential strategic transactions, including possible acquisitions, divestitures, business combinations and mergers.

Between November 2016 and August 2018, Spirit and Frontier periodically explored the possibility of a business combination involving the two companies. Spirit and Frontier entered into a non-disclosure agreement (“NDA”) on November 15, 2016, in connection with discussions between the parties held at such time regarding a potential business combination, which agreement expired by its terms in November 2017. On April 9, 2018, Spirit and Frontier entered into a new NDA in connection with renewed discussions regarding a potential business combination. Spirit and Frontier sent each other “return or destroy” letters on August 22, 2018 and August 24, 2018, respectively, and no confidential information was shared between Spirit and Frontier thereafter until January 2022. The NDA dated April 9, 2018 expired on April 9, 2019.

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On March 31, 2021, Frontier priced an initial public offering of 34.5 million shares of its common stock listed on the Nasdaq Global Select Market, which began trading on April 1, 2021.

On June 8, 2021, William A. Franke, chairman of the board of directors of Frontier and managing member of Indigo Partners, LLC (“Indigo”), an affiliate of the majority stockholder of Frontier, sent an email to Edward M. Christie, Spirit’s President and Chief Executive Officer, and Thomas C. Canfield, Spirit’s Senior Vice President and General Counsel, suggesting an in-person meeting in Fort Lauderdale, Florida. At that meeting, which was held on July 8, 2021, Mr. Franke suggested that the parties consider reopening discussions of a potential business combination, proposing a business combination transaction involving primarily stock consideration. Mr. Christie said he would discuss the matter with the Spirit board of directors. During the course of the conversation, Mr. Franke was asked whether Indigo and Frontier had any preconditions to the potential transaction. Mr. Franke responded that, in light of the challenges generally faced in the consolidation of airlines, Frontier would insist upon a significant level of control over the combined entity. Messrs. Christie and Canfield noted that, given the degree of control that Frontier sought, the consideration to be paid to the Spirit stockholders in any such transaction should include an appropriate premium.

Following this meeting, Mr. Christie sent an email to the Spirit board of directors, covering the matters discussed at the meeting and stating that Spirit management would update its valuation materials and prepare for a discussion at the next meeting of the board, scheduled for August 10, 2021. However, Spirit experienced significant operational disruptions in the first week of August, resulting from a combination of adverse weather events, airport staffing shortages, and flight crew dislocations, and the scheduled board meeting was used exclusively to discuss recovery from the disruptions and schedule adjustments during the remainder of the summer high season.

On August 23, 2021, the Spirit board of directors and senior management team held a scheduled meeting by video conference during which the potential business combination with Frontier was discussed. The Spirit board of directors asked management to have Spirit’s outside advisers refresh their analysis of synergies, but determined that further work on a transaction with Frontier should be put on hold for the time being, in the aftermath of the operating challenges experienced by Spirit in early August.

On August 25, 2021, Messrs. Franke and Christie spoke by telephone and Mr. Christie advised Mr. Franke of Spirit’s decision to defer further discussions on a transaction.

On October 12, 2021, the Spirit board of directors and certain members of the senior management team met in person. The Spirit board of directors received updated summary valuation materials from Spirit’s senior management team and discussed, among other things, the potential value creation and synergies arising from a potential business combination with Frontier, the requisite regulatory approvals necessary for such a transaction, and the location and management of a combined business. The Spirit board of directors directed the Spirit management team to conduct additional analysis of the potential business combination with Frontier and to reach out to Mr. Franke for further discussions.

On October 18, 2021, Mr. Christie emailed Mr. Franke that the Spirit board of directors had authorized further discussions regarding a potential business combination with Frontier. Mr. Christie asked Mr. Franke to identify the key work streams needed from his perspective for purposes of those discussions. Mr. Franke responded by e-mail, noting his desire to understand (1) the impact of a change of control on Spirit’s outstanding indebtedness, (2) Spirit’s fleet and order book, and (3) potential synergies. Mr. Christie responded by e-mail noting that Spirit would like to understand Frontier’s views on relative value, management integration, and fleet plan.

On November 3, 2021, members of Spirit management met by video conference with representatives of Spirit’s financial advisors, Barclays and Morgan Stanley, to discuss financial overviews of the two companies and potential next steps.

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On November 4, 2021, two senior representatives of Morgan Stanley held a meeting with representatives of Indigo Partners in Phoenix, Arizona. The principal purpose of the meeting was to discuss with Indigo Partners the general state of, and opportunities in, the aviation industry in light of the multiple investments Indigo has in the industry. The conversation also included the status of a potential transaction involving Frontier and Spirit.

On November 9, 2021, the Spirit board of directors held a meeting by video conference, during which the Spirit board of directors and members of Spirit’s senior management discussed the potential business combination with Frontier. Representatives of Barclays and Morgan Stanley, and representatives of Spirit’s legal advisor, Debevoise & Plimpton LLP (“Debevoise”), participated in that meeting.

On November 10, 2021, representatives of Morgan Stanley emailed Mr. Franke to advise that the Spirit board of directors had discussed the potential business combination with Frontier and suggested an in-person meeting between Messrs. Franke, Christie, and H. McIntyre Gardner, the chairman of Spirit’s board of directors, to take place later that month.

On November 13, 2021, the Spirit board of directors met by conference call, together with members of Spirit’s senior management and representatives of Barclays and Morgan Stanley, to discuss, among other things, the potential form of merger consideration, potential synergies, transaction expenses, and the potential timing of the consummation of the potential combination. After discussion, a consensus of the Spirit board of directors emerged that a combination of Spirit and Frontier would deliver significant operating synergies and create a more powerful low-fare competitor. The board indicated a preference for an all-stock transaction in which Spirit stockholders would own a share of the combined company “of at least 50%” and could thereby participate meaningfully in the value of synergies. The board agreed that Messrs. Gardner and Christie should set up a call with Mr. Franke to convey this position.

On November 15, 2021, Messrs. Franke, Christie and Gardner held a telephone call during which Messrs. Christie and Gardner proposed to Mr. Franke a stock-for-stock merger between Frontier and Spirit in which the Spirit stockholders would own 50% of the fully-diluted equity of the combined company. Mr. Franke told Messrs. Christie and Gardner that he would have difficulty bridging the gap between a 50% ownership share for Spirit stockholders that they proposed and the significantly lower percentage share of the combined company that the Spirit stockholders would hold if the companies were combined on the basis of the current market capitalizations of the two companies. However, Mr. Franke said he would consider the proposal further and respond more specifically.

On November 18, 2021, Mr. Christie called Mr. Franke. Both noted that the companies’ respective positions on valuation remained apart. No new proposals were made during the call, but they agreed to continue working with their respective boards of directors and advisors and to speak further after the Thanksgiving holiday.

On December 9, 2021, during an executive session associated with a regularly scheduled meeting of the Frontier board of directors, Mr. Franke provided the outside directors with a summary of the recent discussions regarding a transaction with Spirit and the benefits of such a transaction to Frontier if it could be agreed on attractive terms. The directors at the executive session expressed their support for continued discussions with the Spirit representatives. It was also agreed that a meeting of the outside directors would be convened to discuss the transaction in further detail if discussions progressed favorably.

On December 10, 2021, the Spirit board of directors held a scheduled in-person meeting at which the members discussed, among other things, the potential business combination between Spirit and Frontier, including the implied premium if Spirit stockholders were to have a 50% interest in the combined company and the regulatory review process for the transaction. The Spirit board of directors also discussed other aspects of the potential combination, including the stronger competitive position of the combined airline, the fully diluted outstanding share counts of the two companies, and the use of a fixed exchange ratio compared to an adjustable ratio with a possible collar. Mr. Gardner indicated that he and Mr. Christie would schedule an in-person meeting with Mr. Franke to convey the perspective of the Spirit board of directors on the terms of the potential transaction.

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On December 15, 2021, Messrs. Christie and Gardner met in person with Mr. Franke in Dallas, Texas. Messrs. Christie and Gardner again proposed an all-stock transaction in which the Spirit stockholders would own 50% of the fully diluted shares of the combined company. They also noted the need for a broad-based retention program given the potential for a protracted regulatory review period, issues related to labor integration, and the need for both companies to operate independently prior to closing. Mr. Franke indicated that Indigo would be willing to support and recommend to its limited partners and the Frontier board of directors a 47% / 53% ownership split of the combined company between Spirit stockholders and Frontier stockholders, respectively, and that this represented a significant premium to the Spirit stockholders over the then-current market price of Spirit stock. After further discussion, Mr. Franke agreed to present to Indigo’s limited partners and to the Frontier board of directors a transaction that would result in the Spirit stockholders receiving 48.5% of the fully diluted equity of the combined company plus an amount of cash equivalent to 1.5% of the value of the combined company.

On December 17, 2021, Messrs. Christie and Gardner received an email from Mr. Franke outlining a proposal for a business combination in which the Spirit stockholders would receive shares representing a 48% ownership stake in the combined company on a fully diluted basis plus an amount of cash equal to approximately 2% of the value of the combined company. Mr. Franke stated that the current market capitalizations of the two companies indicated an ownership split of 44% for Spirit stockholders and 56% for Frontier stockholders. Mr. Franke also expressed his initial views regarding determination of the brand of the combined company. On December 18, 2021, Mr. Christie shared Mr. Franke’s email with the rest of the Spirit board of directors, along with an updated presentation from Barclays and Morgan Stanley illustrating various ownership scenarios, including the proposals received from Mr. Franke on December 15 and 17.

On December 20, 2021, the Spirit board of directors met by teleconference. After receiving a brief report from Mr. Christie on operations matters during the holiday week, the board reviewed the updated presentation from Spirit’s financial advisors and engaged in a wide-ranging discussion on the potential combination transaction with Frontier. Members of the Spirit board of directors discussed the tight labor market for management talent and expressed concerns over retention and recruiting prior to closing any transaction. They also urged Spirit’s management to continue with the construction of Spirit’s South Florida headquarters and training facility, given that a transaction with Frontier remained uncertain and the new facility would take approximately two years to complete. Sprit’s board members generally agreed that Spirit could accommodate Mr. Franke’s desire that Frontier would hold slightly more than 50% of the stock of the combined company so long as Spirit stockholders received slightly below 50% as well as an amount of cash, taking into account the present value of future synergies, that would result in Spirit stockholders owning not less than 50% of the economic value of the combined business.

On December 27, 2021, Mr. Christie emailed Mr. Franke setting forth a proposal for a business combination pursuant to which (i) the Spirit stockholders would receive shares representing a 48.5% ownership stake in the combined company on a pro forma basis plus $239 million in cash, an amount intended to deliver to the Spirit shareholders an equivalent level of estimated value creation as would have been possible in a 50% / 50% all-stock transaction inclusive of the value of expected synergies to the combined business, (ii) the board of directors of the combined company would have a total of either nine or 11 directors, with Frontier having the right to designate one more director than Spirit, (iii) Mr. Franke would serve as chairman of the board of directors of the combined company, and (iv) Mr. Franke would nominate the chief executive officer of the combined company. Mr. Christie further proposed that determination and public announcement of the brand of the combined company would be made by the board of directors of the combined company following the closing. Mr. Christie also indicated that if the transaction moved forward, Spirit expected to implement an employee retention program in light of the lengthy time anticipated between signing a merger agreement and consummating the transaction.

On January 4, 2022, Messrs. Franke and Christie discussed Spirit’s December 27, 2021 proposal by telephone. Mr. Franke indicated Frontier could recommend the economic terms of that proposal provided that Frontier had the right to designate two more directors to the board of directors of the combined company than Spirit.

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Also on January 4, 2022, the outside directors of Frontier met to discuss the current status of a potential transaction with Spirit. The Frontier directors supported continued pursuit of the business combination with the goal of arriving at definitive terms that the Frontier board of directors could assess.

Later that same day, the Spirit board of directors and members of Spirit’s senior management held a telephonic meeting, with representatives of Barclays, Morgan Stanley and Debevoise present, to discuss the proposed transaction. At that meeting, the Spirit board of directors determined to accept Mr. Franke’s proposal as to the composition of the board of directors of the combined company and otherwise to proceed on the basis of the transaction proposed in Mr. Christie’s email of December 27, 2021. Mr. Christie sent an email to Mr. Franke requesting a call on the following day to discuss other details of the transaction. That e-mail also articulated Spirit’s views on a number of topics of discussion, including board of directors composition and governance matters, the operation of the two airlines during the period between signing and closing, employee retention programs, and the process and timing for the determination of senior management, the location of the headquarters, the brand of the combined company, and related announcements. Mr. Franke articulated Frontier’s view that the brand of the combined company should be announced simultaneously with the announcement of the business combination.

On January 5, 2022, in a phone call with Mr. Franke, Mr. Christie stated that the board of directors split at the combined company, as proposed by Mr. Franke on January 4, was acceptable to Spirit’s board of directors. Mr. Christie also discussed various other matters covered in his email of December 27. On the same day, Mr. Gardner called Mr. Franke to express appreciation for the work undertaken on the Indigo side and the outcome of the parties’ discussions which, he stated, would result in a transaction with significant benefits to both companies. He also discussed aspects of the management and board of directors of the combined company and reconfirmed the Spirit board of directors’ support for continuing to work to finalize the transaction.

On January 6, 2022, Messrs. Franke and Christie spoke by telephone regarding a number of open items, including the calculation of the cash payment and the timing of any public announcement of the brand of the combined company. The following day, Mr. Christie emailed Mr. Franke describing the rationale behind the proposed aggregate cash amount of $239 million. Mr. Christie further proposed that the board of directors of the combined company would determine the brand of the combined company.

On January 7, 2022, Spirit and Frontier entered into an NDA, which contained a customary standstill provision, to facilitate the exchange of confidential information in connection with the parties’ evaluation of the proposed transaction.

On January 8, 2022, Spirit sent a due diligence work plan and document request list to Frontier in advance of a proposed meeting between the parties scheduled for the following week.

From May 2021 to January 2022, representatives of Citi, who were advising Frontier on a potential transaction with Spirit, held meetings with Indigo and members of senior management of Frontier, to discuss such a potential transaction with Spirit. On January 9, 2022, at the direction of Frontier management, representatives of Citi discussed by telephone the approach to determine the appropriate calculation of the equity share count of Spirit with representatives of Barclays and Morgan Stanley.

On January 12 and 13, 2022, members of the senior management of each of Spirit, Frontier and Indigo held in-person meetings in Fort Lauderdale, Florida, and related video and telephonic meetings, to discuss, among other things, due diligence matters, communications strategy, synergies, and transaction costs. Outside financial, legal, and industry advisers of Spirit and Frontier/Indigo participated in portions of these meetings.

On January 13, 2022, Mr. Christie emailed Mr. Franke proposing that Spirit would agree to Frontier being permitted to appoint (i) two more directors to the board of directors of the combined company than Spirit and (ii) the Chief Executive Officer of the combined company. Mr. Christie further proposed that the Chief Executive Officer appointment would be credited against the director appointment allocation of whichever company the Chief Executive served before the transaction.

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On January 17 and 19, 2022, representatives of Debevoise and of Frontier’s legal counsel, Latham & Watkins LLP (“Latham & Watkins”), held telephone calls to discuss the structure of the proposed combination from an income tax perspective.

On January 19, 2022, Spirit sent its five-year plan to Frontier and, on January 20, 2022, representatives of Citi discussed the plan by telephone with representatives of Barclays and Morgan Stanley. On January 20, 2022, representatives of Citi sent Frontier’s five-year plan to Spirit and representatives of Barclays and Morgan Stanley and, on January 21, 2022, members of Spirit’s senior management and representatives of Citi, Barclays and Morgan Stanley discussed the plan by telephone.

Later on January 21, 2022, Latham & Watkins sent Debevoise a draft merger agreement for the proposed transaction. Among other things, that draft provided (i) that the per-share exchange ratio and per-share cash amount to be received by Spirit’s stockholders in the merger would be determined at closing in order to take into account changes in the parties’ respective share counts between the signing of the merger agreement and the closing, (ii) that at the time of signing the merger agreement, Frontier would deliver a consent by Frontier’s majority stockholder, an affiliate of Indigo, approving the issuance of the Frontier common stock in the merger, which consent would become effective only upon the approval of the potential transaction by Spirit’s stockholders (the “Frontier Stockholder Consent”), (iii) “fiduciary out” provisions applicable to each of Spirit and Frontier allowing, among other things, their respective board of directors to terminate the agreement in order to enter into a transaction constituting a “superior proposal,” (iv) mutual termination fees equal to 3.75% of the equity value of Spirit, and (v) restrictions on the operations of Spirit and Frontier between signing of the merger agreement and closing.

On January 24, 2022, the Frontier board of directors met for the purposes of engaging in an extensive status discussion of the potential transaction with Spirit, with representatives from by Citi and Latham & Watkins in attendance. Representatives of Citi reviewed their preliminary financial analyses with the Frontier board of directors. Representatives of Latham & Watkins discussed the fiduciary duties of the members of the Frontier board of directors with respect to the proposed transaction and provided a description of the status of negotiations related to the merger agreement. In advance of the meeting, Citi provided Frontier with information disclosing certain relationships between Citi, Frontier, Spirit, and Indigo Partners LLC, updating the information previously disclosed to Frontier on January 23, 2022.

Also on January 24, 2022, at the direction of Frontier management, representatives of Citi discussed by telephone the approach to the exchange ratio set forth in the draft merger agreement proposed by Frontier with representatives of Barclays and Morgan Stanley.

On January 26, 2022, Debevoise sent Latham & Watkins a revised draft of the merger agreement, which, among other things, (i) contemplated that the exchange ratio and per-share cash amount would be determined at signing of the merger agreement, (ii) provided that the Frontier Stockholder Consent would be effective upon signing (iii) provided for a termination fee equal to 2.75% of the equity value of Spirit, and (iv) modified the restrictions on operations between signing and closing applicable to Spirit and to Frontier.

On January 26 and 27, 2022, members of the senior management of each of Spirit, Frontier, and Indigo met in person in Fort Lauderdale, Florida, with representatives of their respective financial and legal advisors joining portions of the meeting by video conference, to discuss, among other things, the potential synergies expected to result from the proposed transaction, open items in the merger agreement, regulatory and labor matters, and ongoing due diligence.

On January 29, 2022, Latham & Watkins sent Debevoise a revised draft of the merger agreement, which, among other things, (i) contemplated that the exchange ratio would be determined at closing, (ii) provided for the Frontier Stockholder Consent to be effective upon approval of the proposed transaction by Spirit’s stockholders, (iii) reinserted Frontier’s fiduciary out, (iv) provided for a termination fee equal to 3.5% of the equity value of

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Spirit, (v) modified the restrictions on the operations between signing and closing applicable to Spirit and to Frontier, and (vi) proposed that prior to the closing, the board of directors of Frontier (or a committee of such board) would determine the location of the headquarters and the brand of the combined entity and that such decision would not be announced until the earlier of the closing and July 1, 2022.

On January 31, 2022, representatives of Debevoise and Latham & Watkins held a call to discuss the open items in the merger agreement.

On February 1, 2022, Messrs. Christie and Canfield held discussions with Messrs. William Franke and Brian Franke, an executive at Indigo and a member of the Frontier board of directors. It was agreed, among other things, that (i) the termination fee would be set at 3.25% of the equity value of Spirit, (ii) the share exchange ratio would be fixed at signing subject to further issuances of shares prior to closing being constrained to the satisfaction of Frontier, and (iii) the outside date would be up to 24 months following signing, unless further extended by mutual agreement of the parties. The parties also discussed certain changes to the covenants governing interim operations between signing and closing. Additionally, between January 29 and February 4, Mr. Brian Franke had a number of telephone conversations with Messrs. Christie and/or Canfield regarding other commercial terms contained in the draft merger agreement.

On February 2, 2022, the Compensation Committee of the Spirit board of directors and members of Spirit’s senior management held a meeting to discuss a proposal for a retention bonus program and modifications to certain long-term incentive awards of Spirit, in each case, to secure and encourage the continued employment of certain key employees with Spirit following the announcement of the merger.

Also on February 2, 2022, Debevoise sent Latham & Watkins a revised draft of the merger agreement, which, among other things, (i) contemplated that the exchange ratio would be determined at signing, (ii) provided for the Frontier Stockholder Consent to be effective at signing, (iii) removed Frontier’s fiduciary out, (iv) provided for a termination fee equal to 3.25% of the equity value of Spirit, and (v) modified the restrictions on each party’s operations between signing and closing.

On February 3, 2022, the Frontier board of directors met by video conference for the principal purpose of engaging in an extensive discussion of the due diligence review that had been conducted in connection with the potential transaction with Spirit, including the regulatory approvals required in connection with such a business combination. Representatives of Latham & Watkins and members of Frontier’s senior management participated in this discussion. Representatives of Latham & Watkins also provided an update regarding the status of negotiations related to the merger agreement.

Also on February 3, 2022, the compensation committee of Frontier’s board of directors met and approved a policy for employees at the director level or above that provided for the full vesting of an employee’s equity awards if such employee were terminated without “cause” or resigned for “good reason” in connection with a qualifying change in control of Frontier (which would include the merger). The compensation committee of Frontier’s board of directors also approved amending the definition of “change in control” under employees’ existing employment agreements and offer letters for purposes of severance benefits thereunder due upon a qualifying termination of employment in connection with a change in control of Frontier, so that a “change in control” will include the merger. The compensation committee of Frontier’s board of directors also approved the terms of a cash-based retention program for all of Frontier’s salaried, non-union employees based on employee level, which provides for cash payments upon the closing of the merger, subject to a participant’s continued employment through the payment date. The individual cash payments under the program generally range from three months’ salary (for individual contributors and similar level employees) to 150% of an employee’s total cash compensation (for senior vice presidents and above). Participants would be entitled to 50% of their respective retention award if the merger is not consummated.

On February 3, 2022, the Spirit board of directors and members of Spirit’s senior management, with representatives of Barclays, Morgan Stanley, and Debevoise present, held a video conference to discuss the status of the transaction. Spirit’s senior management team provided updates to the Spirit board of directors on the status

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of the merger agreement negotiations. Representatives of Barclays and Morgan Stanley reviewed their respective preliminary financial analyses with the Spirit board of directors. Representatives of Debevoise discussed the fiduciary duties of the members of the Spirit board of directors with respect to the proposed transaction. In advance of the meeting, each of Barclays and Morgan Stanley provided Spirit with updated information on their respective relationships with Spirit, Frontier, and Indigo Partners, LLC.

Later on February 3, 2022, Latham & Watkins sent Debevoise a revised draft of the merger agreement, together with drafts of the exhibits to the merger agreement. The draft merger agreement accepted Spirit’s position reflected in the February 2, 2022 draft merger agreement with respect to the exchange ratio, the effectiveness of the Frontier Stockholder Consent, the absence of a Frontier fiduciary out, the amount of the termination fee, and modifications to the restrictions on Spirit’s and Frontier’s operations between signing and closing. Later that day, Debevoise returned a revised draft of the merger agreement to Latham & Watkins, with revisions relating to termination triggers and the treatment of Spirit’s outstanding equity awards.

On February 4, 2022, representatives of Debevoise and Latham & Watkins had a call to discuss the remaining open items in the merger agreement.

During the morning of February 5, 2022, the Spirit board of directors and members of Spirit’s senior management, with representatives of Barclays, Morgan Stanley, and Debevoise present, held a video conference to review and consider whether to approve the proposed transaction. After referencing its financial analyses provided to the Spirit board of directors in advance of the meeting, each of Barclays and Morgan Stanley rendered its oral opinion (which was subsequently confirmed in writing) to the Spirit board of directors that, as of such date and based upon and subject to the qualifications, limitations, and assumptions stated in its opinion, the merger consideration to be received by the holders of shares of Company common stock (other than the holders of the excluded shares) pursuant to the merger agreement was fair from a financial point of view to such holders of shares of Company common stock. The Spirit board of directors unanimously approved and declared advisable the merger agreement and the transactions contemplated thereby and resolved to recommend that Spirit’s stockholders vote their shares in favor of the adoption of the merger agreement.

In a special sub-session held during the same meeting on February 5, 2022, the Compensation Committee of the Spirit board of directors unanimously approved, subject to approval by the Spirit board of directors of the merger agreement and the transactions contemplated thereby, a retention bonus program for certain key employees of Spirit, including its executive officers, that provides for payment of a cash-based retention award upon the closing of the merger, subject to a participant’s continued employment through such date. For participants who are executive officers of Spirit, the cash payments generally range from a participant’s total cash compensation (for “Vice Presidents”) to 150% of the participant’s total cash compensation (for “Senior Vice Presidents” and above). Participants would be entitled to 50% of their respective retention award in the event that the merger is not consummated. The Compensation Committee of the Spirit board of directors also approved, subject to approval by the Spirit board of directors of the merger agreement and the transactions contemplated thereby, and to any required consent of the holders of the modified long-term incentive awards, modifications to the terms of Spirit time-based cash awards and performance cash awards, and Spirit 2022 PSU Awards, to provide that such awards will be assumed or substituted upon the occurrence of a “change in control” and remain subject to service-based vesting, with any applicable performance conditions treated as having been achieved based on target performance and lapsing upon the “change in control.” If such awards are not assumed or substituted by a successor corporation, or if the holder of an award experiences a qualifying termination following a “change in control,” then the award would vest in full.

Also on February 5, 2022, the Frontier board of directors and members of Frontier’s senior management, with representatives of Citi and Latham & Watkins present, held a video conference to review and consider whether to approve the proposed transaction. After referencing its financial analyses provided to the Frontier board of directors in advance of the meeting, Citi rendered to the Frontier board of directors an oral opinion, confirmed by delivery of a written opinion, dated February 5, 2022, to the effect that, as of that date and based on and subject to various assumptions made, procedures followed, matters considered and limitations and qualifications on the

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review undertaken by Citi as set forth in its written opinion, the exchange ratio, taking into account the cash consideration to be paid by Frontier pursuant to the merger agreement, was fair, from a financial point of view, to Frontier. Representatives of Latham & Watkins described for the Frontier board of directors the modifications to the merger agreement since the discussion held on February 3, 2022. Following these presentations, the Frontier board of directors unanimously approved and declared advisable the merger agreement and the transactions contemplated thereby and resolved to recommend that Frontier’s stockholders approve the issuance of Frontier common stock pursuant to the merger agreement.

Later on February 5, 2022, Spirit and Frontier finalized the merger agreement and the other ancillary agreements, the parties executed the finalized merger agreement, and Indigo executed the Frontier Stockholder Consent.

During the morning of February 7, 2022, Spirit and Frontier issued a joint press release announcing the signing of the transaction, made a joint press appearance, and held a joint investor conference call.

On March 29, 2022, Spirit received an unsolicited proposal from JetBlue Airways Corporation (“JetBlue”) to acquire all of the outstanding shares of Spirit common stock in an all-cash transaction at a price of $33.00 per share (the “JetBlue proposal”), which proposal was subsequently provided to Frontier in accordance with the terms of the merger agreement.

On April 1, 2022, Debevoise called Latham & Watkins to ask whether Frontier was willing to waive the requirement under the merger agreement that the Spirit board of directors determine that the JetBlue proposal constitutes or could be reasonably likely to lead to a “Superior Proposal” (as defined in the merger agreement) before entering into discussions with JetBlue. Later that day, Latham informed Debevoise that Frontier was not willing to waive the requirement.

On April 4, 2022, the Frontier board of directors and members of Frontier’s senior management, with representatives of Citi and Latham & Watkins present, held a video conference to discuss the JetBlue proposal.

On April 7, 2022, the Spirit board of directors and members of Spirit’s senior management, with representatives of Barclays, Morgan Stanley, Debevoise and Spirit’s antitrust counsel, Paul, Weiss, Rifkind, Wharton & Garrison LLP (“Paul Weiss”), present, held a video conference to review the JetBlue proposal. At that meeting, after consultation with its financial advisors and outside counsel, the Spirit board of directors determined that the JetBlue proposal could reasonably be likely to lead to a “Superior Proposal” (as defined in the merger agreement).

The Spirit board of directors directed Spirit’s senior management to negotiate a confidentiality agreement with JetBlue and to engage in discussions with JetBlue with respect to JetBlue’s proposal, in accordance with the terms of the merger agreement. Spirit and JetBlue entered into a confidentiality agreement on April 8, 2022 and commenced discussions regarding the JetBlue proposal on April 9, 2022.

Between April 9, 2022 and April 20, 2022, Paul Weiss conducted seven calls and video conferences with JetBlue’s legal advisor, Shearman & Sterling LLP (“Shearman”), and engaged with economic consultants and economists in order to assess the regulatory risk of an acquisition of Spirit by JetBlue and to assess the validity and merits of JetBlue’s own analysis.

On April 13, 2022, Frontier and Spirit received second requests for information from the DOJ in connection with the proposed merger with Frontier.

On April 14, 2022, Mr. Christie and Mr. Franke had lunch together in Phoenix, Arizona, which had been scheduled in mid-March prior to the JetBlue proposal, but did not discuss either the JetBlue proposal or the proposed merger with Frontier.

On April 15, 2022, Spirit provided JetBlue and its representatives with access to a virtual data room containing due diligence materials for Spirit.

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On April 19, 2022, members of senior management of Spirit and JetBlue, together with their respective financial advisors, held a video conference to discuss a broad range of financial and business due diligence matters.

On April 21, 2022, the Spirit board of directors and members of Spirit’s senior management, with representatives of Barclays, Morgan Stanley, Debevoise and Paul Weiss present, held a video conference to discuss the JetBlue proposal. The discussion focused primarily on the likelihood of a transaction with JetBlue receiving the requisite regulatory approvals needed to consummate the transaction and the risks to Spirit’s business during a likely protracted approval period. The Spirit board of directors directed Spirit’s senior management and legal advisors to develop a proposal to convey to JetBlue in respect of the contractual protections that Spirit would need to improve the likelihood that the JetBlue proposal could be consummated.

On April 24, 2022, the Spirit board of directors and members of Spirit’s senior management, with representatives of Barclays, Morgan Stanley, Debevoise and Paul Weiss present, held a video conference to further discuss the JetBlue proposal. At that meeting, the Spirit board of directors instructed Spirit’s senior management to communicate to JetBlue a package of contractual protections that the board of directors considered appropriate to provide increased assurance as to the likelihood of regulatory approval of the JetBlue proposal and to protect Spirit and its stockholders against the risk that such approval would not be obtained, which included a covenant to take all actions necessary to obtain regulatory approval, including being willing to terminate JetBlue’s Northeast Alliance Agreement (“NEA”) with American Airlines and make any divestitures necessary to obtain regulatory approval, and a significant reverse termination fee payable in the event that such regulatory approval ultimately was not obtained. The Spirit board of directors also instructed Spirit’s senior management to inform JetBlue that, in the event that Spirit ultimately concluded that the JetBlue proposal, as it might be amended, constituted a Superior Proposal, Spirit would expect JetBlue to fund the termination fee payable to Frontier upon termination of the Frontier merger agreement.

On April 25, 2022, Mr. Christie called Mr. Hayes to convey the foregoing package of contractual protections. Following that discussion, representatives from Barclays and Morgan Stanley held a call with JetBlue’s financial advisor, Goldman Sachs Group Inc. (“Goldman”), to discuss the same proposal, and Debevoise delivered to Shearman a document setting forth Spirit’s proposal along with proposed language for the regulatory covenant that Spirit would expect to be included in any merger agreement with JetBlue.

On April 29, 2022, JetBlue sent Spirit a letter setting forth its response to Spirit’s proposed package of contractual protections to address the regulatory approval risks inherent in the JetBlue proposal, along with a draft of a merger agreement between JetBlue and Spirit. In that response, JetBlue offered (i) to pay a reverse termination fee of $200 million if antitrust approval was not obtained, (ii) to use its reasonable best efforts to obtain regulatory approval subject to various limitations, including that JetBlue would not be required to take any action that in its sole and absolute discretion would be reasonably likely to materially and adversely affect the anticipated benefits of JetBlue or American Airlines under the NEA or that would have a material adverse effect on Spirit or JetBlue when measured relative to a company of Spirit’s size, and (iii) to fund the termination fee payable to Frontier upon termination of the Frontier merger agreement.

On April 30, 2022, the Spirit board of directors and members of Spirit’s senior management, with representatives of Barclays, Morgan Stanley, Debevoise and Paul Weiss present, held a video conference to discuss the JetBlue proposal, as modified by the April 29, 2022 letter. The Spirit board of directors’ discussion focused on the prospects that the JetBlue proposal would be able to obtain regulatory approval, particularly in light of JetBlue’s unwillingness to abandon the NEA, and the requirement of the Frontier merger agreement that, in order for an Acquisition Proposal to constitute a Superior Proposal, it must be “reasonably capable of being consummated in accordance with the terms of such Acquisition Proposal, taking into account all financial, regulatory, legal and other aspects of such Acquisition Proposal.” The Spirit board of directors also discussed the extended time that would be required to reach a final regulatory determination, which was expected to be up to two years, and the risks to Spirit if it were unable to complete the proposed transaction with JetBlue at the end of that period.

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Following adjournment, the Spirit board of directors continued its meeting on May 1, 2022. The directors, other than Mr. Christie, initially met in executive session together with representatives of Debevoise, after which Mr. Christie, other members of Spirit’s senior management, and representatives of Barclays, Morgan Stanley and Paul Weiss joined the meeting. Following further discussion among the board and its advisors, the Spirit board of directors unanimously determined that the JetBlue proposal did not constitute a “Superior Proposal” as defined in the Frontier merger agreement, on the basis that it did not meet the requirement of being reasonably capable of being consummated. In reaching that determination, the Spirit board of directors took into account, among other things, the low probability that the JetBlue proposal would receive antitrust clearance so long as the NEA remained in effect, the ongoing litigation brought against JetBlue and American Airlines by the DOJ and the Attorneys General of six states and the District of Colombia seeking to block the NEA on the grounds that it eliminated competition and harmed air travel consumers, the Spirit board of directors’ belief that the divestitures proposed by JetBlue would not be sufficient to resolve the DOJ’s objections to the NEA or its expected objection to a combination of JetBlue and Spirit, and the fact that the reverse termination fee proposed by JetBlue would not be adequate to protect Spirit’s stockholders against the substantial risk that the JetBlue proposal would not receive regulatory approval. Given the Spirit board of directors’ determination that the JetBlue proposal failed to satisfy the portion of the definition of “Superior Proposal” requiring it to be reasonably capable of consummation, the Spirit board of directors did not form a view as to whether the economic terms of the JetBlue proposal were or were not more favorable to the Spirit stockholders, from a financial point of view, than the economic terms of the Frontier merger agreement.

On May 2, 2022, Spirit sent a letter to JetBlue, which Spirit also released publicly, informing JetBlue that the Spirit board of directors had determined that the JetBlue proposal did not constitute a “Superior Proposal” as defined in the Frontier merger agreement, on the grounds that it was not reasonably capable of being consummated, and that the Spirit board of directors continued to believe that the pending transaction with Frontier represented the best opportunity to maximize value for the Spirit stockholders.

Frontier’s Reasons for the Merger

In evaluating the merger, the Frontier board of directors consulted with Frontier management, as well as independent legal and financial advisors, and, in the course of reaching its decision to (i) approve and declare advisable the merger agreement, the merger and other transactions contemplated thereby and (ii) subject to the terms and conditions of the merger agreement, recommend that the Frontier stockholders approve the issuance of Frontier common stock, the Frontier board of directors considered a number of factors, including the following material factors:

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In the course of its deliberations, the Frontier board of directors also considered the following risks and other countervailing factors related to entering into the merger agreement that had previously been identified and discussed by Frontier management and the Frontier board of directors:

The foregoing discussion of the information and factors considered by Frontier’s board of directors is not intended to be exhaustive, but includes the material factors considered by Frontier’s board of directors. In reaching its decision to approve and declare advisable the merger agreement, the merger and other transactions contemplated thereby, Frontier’s board of directors did not quantify or assign any relative weight to the factors considered, and individual directors may have given different weights to different factors. Frontier’s board of directors considered all these factors as a whole and overall considered the factors to be favorable to, and to support, its determination.

For the reasons set forth above, the Frontier board of directors unanimously (i) determined that the merger and other transactions contemplated by the merger agreement are fair to and in the best interest of Frontier and its stockholders, (ii) approved and declared advisable the merger agreement, the merger and other transactions contemplated thereby and (iii) subject to the terms and conditions of the merger agreement, recommended that the Frontier stockholders approve the issuance of Frontier common stock. The written consent of Frontier’s major stockholder approving the issuance of Frontier common stock in connection with the merger as contemplated by the merger agreement was obtained on February 5, 2022.

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Unaudited Prospective Financial Information

Frontier Financial Forecasts

Other than limited short-term guidance concerning certain aspects of their expected financial performance which is publicly issued each quarter, Frontier does not as a matter of course make public projections as to future performance, revenues, earnings or other financial results given, among other reasons, the uncertainty of realizing the underlying assumptions and estimates. However, Frontier is including in this information statement and proxy statement/prospectus certain unaudited prospective financial information, which are summarized in the below table (which we refer to as the “Frontier Financial Forecasts”), that was provided to the Frontier board of directors in connection with its evaluation of the merger and to Citi, financial advisor to Frontier, for purposes of its financial analysis and opinion described in the section titled “The Merger—Opinion of Citigroup Global Markets Inc.”. The Frontier Financial Forecasts were also provided to Spirit and to Morgan Stanley and Barclays, financial advisors to Spirit.

The Frontier Financial Forecasts were prepared based on the following key forecast assumptions:

The inclusion of this information should not be regarded as an indication that any of Frontier, Spirit, their respective affiliates, officers, directors, advisors or other representatives or any other recipient of this information considered, or now considers, it necessarily to be predictive of actual future results, or that it should be construed as financial guidance, and it should not be relied on as such. This information was prepared solely for internal use, is subjective in many respects and has not been updated since the time of preparation in January 2022.

The following table sets forth the estimated amounts of the Unlevered Free Cash Flow of Frontier, calculated using the above prospective financial information as approved by Frontier management for use by Citi in connection with its

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financial analysis and opinion described in the section of this information statement and proxy statement/prospectus captioned “The Merger—Opinion of Citigroup Global Markets Inc.” (amounts may reflect rounding):

The following table sets forth the estimated amounts of the Unlevered Free Cash Flow of Frontier, calculated using the above prospective financial information as approved by Spirit management for use by Barclays and Morgan Stanley for purposes of their respective financial analyses and opinions described in the sections of this information statement and proxy statement/prospectus captioned “The Merger—Opinion of Barclays Capital Inc.” and “The Merger—Opinion of Morgan Stanley & Co. LLC” (amounts may reflect rounding):

Spirit Financial Forecasts

Other than limited short-term guidance concerning certain aspects of their expected financial performance which is publicly issued each quarter, Spirit does not as a matter of course make public projections as to future performance, revenues, earnings or other financial results given, among other reasons, the uncertainty of realizing the underlying assumptions and estimates. However, Spirit is including in this information statement and proxy statement/prospectus certain unaudited prospective financial information, which are summarized in the below table (which we refer to as the “Spirit Financial Forecasts”), that was provided to the Spirit board of directors in connection with their evaluation of the merger and to Barclays and Morgan Stanley, financial advisors to Spirit, for purposes of their respective financial analyses and opinions described in the sections of this information statement and proxy statement/prospectus captioned “The Merger—Opinion of Barclays Capital Inc.” and “The Merger—Opinion of Morgan Stanley & Co. LLC”. The Spirit Financial Forecasts were also provided to Frontier and to Citi, financial advisor to Frontier.

The Spirit Financial Forecasts were prepared based on the following key forecast assumptions:

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The inclusion of this information should not be regarded as an indication that any of Frontier, Spirit, their respective affiliates, officers, directors, advisors or other representatives or any other recipient of this information considered, or now considers, it necessarily to be predictive of actual future results, or that it should be construed as financial guidance, and it should not be relied on as such. This information was prepared solely for internal use and is subjective in many respects.

The following table sets forth the estimated amounts of the Unlevered Free Cash Flow of Spirit, calculated using the above prospective financial information as approved by Spirit management for use by Barclays and Morgan Stanley for purposes of their respective financial analyses and opinions described in the section of this information statement and proxy statement/prospectus captioned “The Merger—Opinion of Barclays Capital Inc.” and “The Merger—Opinion of Morgan Stanley & Co. LLC” (amounts may reflect rounding):

The following table sets forth the estimated amounts of the Unlevered Free Cash Flow of Spirit, calculated using the above prospective financial information as approved by Frontier management for use by Citi in connection with its financial analysis and opinion described in the section of this information statement and proxy statement/prospectus captioned “The Merger — Opinion of Citigroup Global Markets Inc.” (amounts may reflect rounding):

Synergy Forecasts

In addition, in connection with the evaluation of the merger, Frontier and Spirit jointly developed estimates of synergies that could be achieved by the combined company in connection with the merger, which are summarized in the below table (which we refer to as the “Synergy Forecasts”). Frontier and Spirit are electing to provide the Synergy Forecasts in this section of the information statement and proxy statement/prospectus to provide each of Frontier’s and Spirit’s stockholders access to the Synergy Forecasts that were made available to each of the Frontier and Spirit board of directors, for purposes of considering and evaluating the merger, as well as each company’s financial advisors, for purposes of their respective financial analyses and opinions. The inclusion of this information should not be regarded as an indication that any of Frontier, Spirit, their respective

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affiliates, officers, directors, advisors or other representatives or any other recipient of this information considered, or now considers, it necessarily to be predictive of actual future results, or that it should be construed as financial guidance, and it should not be relied on as such. This information was prepared solely for internal use and is subjective in many respects.

Important Information About the Financial Forecasts

The Frontier Financial Forecasts, the Spirit Financial Forecasts, and the Synergy Forecasts (which we refer to collectively as the “Financial Forecasts”) provide summary unaudited prospective financial information for Frontier, Spirit, and the combined company. The Financial Forecasts were not prepared with a view toward public disclosure and the inclusion of such Financial Forecasts should not be regarded as an indication that any of Frontier, Spirit, or any other recipient of this information considered, or now considers, it to be necessarily predictive of actual future results.

While presented with numeric specificity, the Financial Forecasts were not prepared for purposes of public disclosure, nor were they prepared on a basis designed to comply with GAAP published guidelines of the SEC or the guidelines established by the American Institute of Certified Public Accountants for preparation and presentation of projections. However, in the view of Frontier management and Spirit management, the respective Financial Forecasts were prepared on a reasonable basis, and reflect the best currently available estimates and judgments, and present, to the best of Frontier management’s and Spirit management’s knowledge and belief, the expected course of action and the expected future financial performance of Frontier and Spirit, respectively. Neither Frontier’s independent registered public accounting firm nor Spirit’s independent registered public accounting firm, each of which is listed as an expert in the section entitled “Experts” of this information statement and proxy statement/prospectus, nor any other independent accountants, compiled, examined or performed any procedures with respect to the Financial Forecasts summarized above, and has not expressed any opinion or any other form of assurance on this information or its achievability, and assumes no responsibility for, and disclaims any association with, the Financial Forecasts. The reports of the independent registered public accounting firms incorporated by reference in this information statement and proxy statement/prospectus relate to historical financial statements. They do not extend to any financial projections and should not be seen to do so.

Although presented with numerical specificity, the Financial Forecasts were prepared in accordance with variables, estimates, and assumptions that are inherently uncertain and may be beyond the control of Frontier and Spirit, and which may prove not to have been, or to no longer be, accurate. While in the view of Frontier and Spirit management the Financial Forecasts were prepared on a reasonable basis, the Financial Forecasts are subject to many risks and uncertainties. Important factors that may affect actual results and cause actual results to differ materially from the Financial Forecasts include risks and uncertainties relating to Frontier’s and Spirit’s businesses, industry performance, the regulatory environment, general business and economic conditions, market and financial conditions, various risks set forth in Frontier’s and Sprit’s reports filed with the SEC, and other factors described or referenced in the sections entitled “Risk Factors” and “Cautionary Statement Regarding Forward-Looking Statements” of this information statement and proxy statement/prospectus.

The Financial Statements also reflect assumptions that are subject to change and are susceptible to multiple interpretations and to conditions, transactions or events that may occur and were not anticipated at the time the Financial Forecasts were prepared. In addition, the Financial Forecasts do not take into account any circumstances, transactions or events occurring after the date the Financial Forecasts were prepared. Accordingly, actual results will likely differ, and may differ materially, from those contained in the Financial Forecasts. We do not assure you that the financial results in the Financial Forecasts set forth above will be realized or that future financial results of Frontier or Spirit will not materially vary from those in the Financial Forecasts.

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None of Frontier, Spirit, or their respective affiliates, officers, directors, or other representatives gives any stockholder of Frontier or Spirit, or any other person, any assurance that actual results will not differ materially from the Financial Forecasts, and, except as otherwise required by law, none of them undertakes any obligation to update or otherwise revise or reconcile the Financial Forecasts to reflect circumstances after the date the Financial Forecasts were generated or to reflect the occurrence of future events, even in the event that any or all of the assumptions and estimates underlying the Financial Forecasts are shown to be in error.

No one has made or makes any representation to any stockholder of Frontier or Spirit, or anyone else regarding, nor assumes any responsibility for the validity, reasonableness, accuracy, or completeness of, the Financial Forecasts set forth above. You are cautioned not to rely on the Financial Forecasts. The inclusion of this information should not be regarded as an indication that the Frontier board, the Spirit board, any of their advisors or any other person considered, or now considers, it to be material or to be a reliable prediction of actual future results.

The Financial Forecasts included above cover multiple years, and this information by its nature becomes subject to greater uncertainty with each successive year. The Financial Forecasts should be evaluated, if at all, in conjunction with the historical financial statements and other information contained in Frontier’s and Spirit’s respective public filings with the SEC.

Due to the forward-looking nature of the Financial Forecasts, specific quantifications of the amounts that would be required to reconcile it to GAAP measures are not available. Frontier and Spirit believe that there is a degree of volatility with respect to certain GAAP measures, and certain adjustments made to arrive at the relevant non-GAAP measures, which preclude Frontier and Spirit from providing accurate forecasted non-GAAP to GAAP reconciliations.

Opinion of Citigroup Global Markets Inc.

Frontier retained Citi as its financial advisor in connection with a possible transaction involving Spirit. In connection with Citi’s engagement, Frontier requested that Citi evaluate the fairness, from a financial point of view, to Frontier of the exchange ratio, taking into account the cash consideration to be paid by Frontier pursuant to the merger agreement. On February 5, 2022, at a meeting of the Frontier board held to evaluate the proposed merger and at which the merger agreement was approved, Citi rendered to the Frontier board an oral opinion, confirmed by delivery of a written opinion, dated February 5, 2022, to the effect that, as of that date and based on and subject to various assumptions made, procedures followed, matters considered and limitations and qualifications on the review undertaken by Citi as set forth in its written opinion, the exchange ratio, taking into account the cash consideration to be paid by Frontier pursuant to the merger agreement, was fair, from a financial point of view, to Frontier.

The full text of Citi’s written opinion, dated February 5, 2022, to the Frontier board, which sets forth, among other things, the assumptions made, procedures followed, matters considered and limitations and qualifications on the review undertaken by Citi in rendering its opinion, is attached to this information statement and proxy statement/prospectus as Annex B and is incorporated herein by reference in its entirety. The summary of Citi’s opinion set forth below is qualified in its entirety by reference to the full text of Citi’s opinion. Citi’s opinion was rendered to the Frontier board (in its capacity as such) in connection with its evaluation of the proposed merger and was limited to the fairness, from a financial point of view, as of the date of the opinion, to Frontier of the exchange ratio, taking into account the cash consideration to be paid by Frontier pursuant to the merger agreement. Citi’s opinion did not address any other terms, aspects or implications of the proposed merger. Citi’s opinion is not intended to be and does not constitute a recommendation to any stockholder as to how such stockholder should vote or act on any matters relating to the proposed merger.

In arriving at its opinion, Citi:

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In addition to the forgoing, Citi conducted such other analyses and examinations and considered such other information and financial, economic and market criteria as Citi deemed appropriate in arriving at its opinion. The issuance of Citi’s opinion had been authorized by Citi’s fairness opinion committee.

In rendering its opinion, Citi had assumed and relied, without independent verification, upon the accuracy and completeness of all financial and other information and data publicly available or provided to or otherwise reviewed by or discussed with Citi and upon the assurances of the management of Frontier that they were not aware of any relevant information that had been omitted or that remained undisclosed to Citi. With respect to financial forecasts and other information and data relating to Spirit which were provided to or discussed with Citi by the management of Spirit, and which Frontier had directed Citi to use for purposes of its analysis and the opinion, Citi had been advised by the management of Spirit and had assumed, with Frontier’s consent, that, they were reasonably prepared in good faith on bases reflecting the best currently available estimates and judgments of the management of Spirit as to the future financial performance of Spirit, and had assumed, with Frontier’s consent, that the financial results reflected in such forecasts and other information and data would be realized in the amounts and at the times projected. With respect to financial forecasts and other information and data relating to Frontier and Spirit which were provided to or discussed with Citi by the management of Frontier, including the potential Synergies anticipated by the managements of Frontier and Spirit to result from the merger, Citi had been advised by the management of Frontier and had assumed, with Frontier’s consent, that such forecasts and potential Synergies and other information and data were reasonably prepared in good faith on bases reflecting the best currently available estimates and judgments of the management of Frontier as to the future financial performance of Frontier, including the potential Synergies and the other matters covered thereby, and had assumed, with Frontier’s consent, that the financial results (including the potential Synergies) reflected in such forecasts and other information and data would be realized in the amounts and at the times projected. In addition, Citi relied, at Frontier’s direction, upon the assessments of the management of Frontier, as to, among other things, (i) the potential impact on Frontier and Spirit of certain market, competitive, cyclical and other trends and developments in and prospects for, and governmental, regulatory and legislative matters relating to or otherwise affecting, the airline industry, including assumptions of the management of Frontier as to, among other things, future fuel prices, operational, maintenance and other costs, and demand for air travel reflected in the financial forecasts and other information and data utilized in its analysis or otherwise relevant for purposes of its opinion, which were subject to significant volatility and which, if different than as assumed, could have had a material impact on its analyses and opinion, (ii) existing and future relationships, agreements and arrangements with, and

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the ability to attract, retain and/or replace, key employees, customers, suppliers and other commercial relationships of Frontier and Spirit, and (iii) the ability of Frontier to integrate the businesses and operations of Frontier and Spirit and to realize the potential Synergies anticipated by the management of Frontier to result from the merger. Citi had assumed, with Frontier’s consent, that there would be no developments with respect to any such matters that would have an adverse effect on Frontier and Spirit or the merger (including the contemplated benefits thereof) or that otherwise would be meaningful in any respect to its analyses or opinion. Citi expressed no opinion as to any financial and other information or data (or any underlying assumptions on which any such financial and other information or data are based) provided to or otherwise reviewed by or discussed with Citi.

Citi had assumed, with Frontier’s consent, that the merger would be consummated in accordance with its terms, without waiver, modification or amendment of any material term, condition or agreement and that, in the course of obtaining the necessary regulatory or third party approvals, consents and releases for the merger, no delay, limitation, restriction or condition would be imposed that would have an adverse effect on Frontier, Spirit or the contemplated benefits of the merger that would be material to Citi’s analysis or opinion. Citi did not express any opinion or view with respect to accounting, tax, regulatory, legal or similar matters and Citi had relied, with Frontier’s consent, upon the assessments of representatives of Frontier as to such matters.

Citi’s opinion did not address any terms (other than the exchange ratio, taking into account the cash consideration to be paid by Frontier pursuant to the merger agreement, to the extent expressly specified therein), aspects or implications of the merger, including, without limitation, the form or structure of the merger, any consent, indemnification, escrow, holdback or other agreement, arrangement or understanding to be entered into in connection with, related to or contemplated by the merger or otherwise. Citi’s opinion, as set forth therein, related to the relative values of Frontier and Spirit (taking into account the cash consideration to be paid by Frontier pursuant to the merger agreement). Citi did not express any opinion as to what the value of the Frontier common stock actually would be when issued pursuant to the merger or the prices at which the Frontier common stock or Spirit common stock would trade at any time. Citi’s opinion was limited to the fairness, from a financial point of view, of the exchange ratio, taking into account the cash consideration to be paid by Frontier pursuant to the merger agreement. Citi had not made or been provided with an independent evaluation or appraisal of the assets or liabilities (contingent or otherwise) of Frontier or Spirit nor had it made any physical inspection of the properties or assets of Frontier or Spirit. Citi expressed no view as to, and its opinion does not address, the underlying business decision of Frontier to effect or enter into the merger, the relative merits of the merger as compared to any alternative business strategies that might exist for Frontier or the effect of any other transaction in which Frontier might engage or consider. Citi also expressed no view as to, and its opinion does not address, the fairness (financial or otherwise) of the amount or nature or any other aspect of any compensation or other consideration to any officers, directors or employees of any parties to the merger, or any class of such persons, relative to the exchange ratio, taking into account the cash consideration to be paid by Frontier pursuant to the merger agreement, or otherwise. Citi’s opinion was necessarily based upon information available to it, and financial, stock market and other conditions and circumstances existing and disclosed to Citi, as of the date of its opinion. Although subsequent developments may have affected its opinion, Citi had no obligation to update, revise or reaffirm its opinion. As Frontier was aware, the credit, financial and stock markets, and the industries and sectors in which Frontier and Spirit operate, had experienced and continue to experience volatility and Citi expressed no opinion or view as to any potential effects of such volatility on Frontier, Spirit (or their respective businesses) or the merger (including the contemplated benefits thereof).

In preparing its opinion, Citi performed a variety of financial and comparative analyses, including those described below. The preparation of a financial opinion is a complex analytical process involving various determinations as to the most appropriate and relevant methods of financial analysis and the application of those methods to the particular circumstances and, therefore, a financial opinion is not readily susceptible to partial analysis or summary description. Citi arrived at its opinion based on the results of all analyses undertaken by it and factors assessed as a whole, and it did not draw, in isolation, conclusions from or with regard to any one factor or method of analysis for purposes of its opinion.

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The estimates used by Citi for purposes of its analyses and the valuation ranges resulting from any particular analysis are not necessarily indicative of actual values or predictive of future results or values, which may be significantly more or less favorable than those suggested by such analyses. In addition, analyses relating to the value of businesses or securities do not purport to be appraisals or to reflect the prices at which businesses or securities actually may be sold or acquired. Accordingly, the estimates used in, and the results derived from, Citi’s analyses are inherently subject to substantial uncertainty.

Citi was not requested to, and it did not, recommend or determine the specific consideration payable in the proposed merger. The type and amount of consideration payable in the proposed merger were determined through negotiations between Frontier and Spirit and Frontier’s decision to enter into the merger agreement was solely that of the Frontier board. Citi’s opinion was only one of many factors considered by the Frontier board in its evaluation of the proposed merger and should not be viewed as determinative of the views of the Frontier board or the management of Frontier with respect to the proposed merger, the exchange ratio or any other aspect of the transactions contemplated by the merger agreement.

Summary of Financial Analyses of Citi

The following is a summary of the material financial analyses prepared for and reviewed with the Frontier board in connection with the rendering of Citi’s opinion, dated February 5, 2022, to the Frontier board. The summary set forth below does not purport to be a complete description of the financial analyses performed by, and underlying the opinion of Citi, nor does the order of the financial analyses described represent the relative importance or weight given to those financial analyses by Citi. Certain financial analyses summarized below include information presented in tabular format. In order to fully understand the financial analyses, the tables must be read together with the text of each summary as the tables alone do not constitute a complete description of the financial analyses. Considering the data in the tables below without considering the full narrative description of the financial analyses, including the methodologies and assumptions underlying the financial analyses, could create a misleading or incomplete view of such financial analyses. Future results may be different from those described and such differences may be material. Financial data utilized for Frontier and Spirit in the financial analyses described below, to the extent based on financial forecasts and estimates of management, were based on (i) certain financial forecasts and other information and data relating to Spirit provided to or discussed with Citi by the management of Spirit, and approved for Citi’s use by Frontier, as further summarized in the section entitled “The Merger—Unaudited Prospective Financial Information” beginning on page 73 (which we refer to as the “Spirit Management Projections”) and (ii) certain financial forecasts and other information and data relating to Frontier and Spirit, including information relating to potential revenue enhancements, cost savings and other strategic implications and financial and operational benefits (including the amount, timing and achievability thereof) anticipated by the management of Frontier to result from the merger, provided to or discussed with Citi by the management of Frontier and approved for Citi’s use by Frontier, as further summarized in the section entitled “The Merger—Unaudited Prospective Financial Information” beginning on page 73 (which we refer to as the “Frontier Management Projections”). In addition, the approximate implied per share equity value reference ranges derived from the financial analyses described below, except for the 52-week trading range, were rounded to the nearest $0.05.

In calculating implied exchange ratio reference ranges as reflected in the financial analyses described below, Citi divided the low-ends (or high-ends, as the case may be) of the approximate implied per share equity value reference ranges derived for Spirit from such analyses, after taking into account the cash consideration to be paid by Frontier pursuant to the merger agreement, by the high-ends (or low-ends, as the case may be) of the approximate implied per share equity value reference ranges derived for Frontier from such analyses in order to calculate the low-ends (or high-ends) of the implied exchange ratio reference ranges.

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Discounted Cash Flow Analyses

Citi performed separate discounted cash flow analyses of Spirit and Frontier. A discounted cash flow analysis is designed to estimate an implied value of a company by calculating the present value of the estimated future unlevered after-tax free cash flows of that company over a projection period and a terminal value for that company at the end of the projection period.

Spirit

Citi conducted discounted cash flow analyses for Spirit using the Spirit Management Projections. For purposes of its analysis, Citi used estimates of the unlevered free cash flows that Spirit was forecasted to generate during the period from January 1, 2022 through December 31, 2026, as provided in the Spirit Management Projections. Citi also calculated a range of terminal values for Spirit, by applying an illustrative range of perpetuity growth rates of 2.5% to 3.5% to estimates of the unlevered free cash flows that Spirit was expected to generate in the terminal year as provided by Frontier management. The unlevered free cash flows and the range of terminal values were then discounted to present values, as of December 31, 2021, using mid-period discounting convention and discount rates ranging from 10.4% to 11.9%, to derive ranges of implied firm value for Spirit. The illustrative range of perpetuity growth rates applied was selected by Citi based on its professional judgment and experience. The discount rate range was chosen by Citi based upon an analysis of the weighted average cost of capital of Spirit, which Citi performed utilizing the capital asset pricing model with inputs that Citi determined were relevant based on publicly available data and Citi’s professional judgment.

From the range of implied firm values it derived for Spirit, Citi subtracted Spirit’s net debt as of December 31, 2021 (calculated as debt, excluding in-the-money convertible notes, less cash and cash equivalents, excluding cash to settle in-the-money convertible notes) and added a range of present values of Spirit’s tax benefits from Federal net operating losses carry forwards, and divided the results by diluted share counts of Spirit calculated using the treasury stock method, based on equity information as of February 4, 2022 as provided by Spirit management. The range of present values of Spirit’s tax benefits from Federal net operating losses carry forwards was calculated by discounting to present values, as of December 31, 2021, estimates of Spirit’s tax benefits from Federal net operating losses carry forwards, as provided in the Spirit Management Projections, using end of period discounting convention and discount rates ranging from 10.4% to 11.9%, which Citi derived from a calculation of the weighted average cost of capital of Spirit.

This analysis indicated an approximate implied per share equity value reference range for Spirit of $49.35 to $68.95, as compared to the closing share price of the Spirit common stock as of February 4, 2022, of $21.73, and the implied per share value of the merger consideration, of $25.83 (calculated as the cash consideration of $2.13 per share of Spirit common stock plus the exchange ratio of 1.9126x multiplied by the closing price per share of Frontier common stock as of February 4, 2022 of $12.39).

Frontier

Citi conducted discounted cash flow analyses for Frontier using the Frontier Management Projections. For purposes of its analysis, Citi used estimates of the unlevered free cash flows that Frontier was forecasted to generate during the period from January 1, 2022 through December 31, 2026, as provided in the Frontier Management Projections. Citi also calculated a range of terminal values for Frontier, by applying an illustrative range of perpetuity growth rates of 2.5% to 3.5% to estimates of the unlevered free cash flows that Frontier was expected to generate in the terminal year as provided by Frontier management. The unlevered free cash flows and the range of terminal values were then discounted to present values, as of December 31, 2021, using mid-period discounting convention and discount rates ranging from 10.5% to 12.0%, to derive ranges of implied firm value for Frontier. The illustrative range of perpetuity growth rates applied was selected by Citi based on its professional judgment and experience. The discount rate range was chosen by Citi based upon an analysis of the weighted average cost of capital of Frontier, which Citi performed utilizing the capital asset pricing model with inputs that Citi determined were relevant based on publicly available data and Citi’s professional judgment.

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From the range of implied firm values it derived for Frontier, Citi subtracted Frontier’s net debt as of December 31, 2021 (calculated as debt less cash) and added a range of present values of Frontier’s tax benefits from Federal net operating losses carry forwards, and divided the results by diluted share counts of Frontier calculated using the treasury stock method, based on equity information as of February 4, 2022 as provided by Frontier management. The range of present values of Frontier’s tax benefits from Federal net operating losses carry forwards was calculated by discounting to present values, as of December 31, 2021, estimates of Frontier’s tax benefits from Federal net operating losses carry forwards, as provided in the Frontier Management Projections, using end of period discounting convention and discount rates ranging from 10.5% to 12.0%, which Citi derived from a calculation of the weighted average cost of capital of Frontier.

This analysis indicated an approximate implied per share equity value reference range for Frontier of $22.50 to $29.30, as compared to the closing share price of the Frontier common stock, as of February 4, 2022, of $12.39.

Selected Public Companies Analyses

Citi performed separate selected public companies analyses of Spirit and Frontier, in each case, on a standalone basis, in which Citi reviewed certain financial and stock market information relating to Spirit, Frontier and the selected publicly traded companies listed below.

Spirit

Citi reviewed certain publicly available financial and stock market information of Spirit and the following selected companies (which we collectively refer to as the “Spirit selected companies”):

Although none of the Spirit selected companies listed above is directly comparable to Spirit, the companies included were chosen because they have operations that, for purposes of Citi’s analysis and based on its experience and professional judgment, may be considered generally relevant in evaluating those of Spirit based on business sector participation, operational characteristics and financial metrics. The quantitative information used in this analysis, to the extent that it is based on market data, was based on market data as of February 4, 2022.

For each of the Spirit selected companies, and for Spirit for reference, Citi calculated and reviewed, among other information, (i) price as a multiple of calendar year 2023 estimated adjusted earnings per share (which we refer to as “EPS”, and such multiple as “Price / 2023E EPS”); and (ii) firm value (calculated as fully diluted market equity value, plus net debt, operating lease liabilities, preferred equity and non-controlling interests, and less unconsolidated investments, as applicable) as a multiple of estimated calendar year 2023 adjusted earnings before interest, taxes, depreciation, amortization and rent costs (which we refer to as “EBITDAR” and such multiple as “Firm Value / 2023E EBITDAR”). Financial data of the Spirit selected companies were based on Wall Street research analysts’ estimates and other publicly available information. With respect to the multiples calculated for Spirit for reference, the financial data of Spirit was based on Wall Street research analysts’ estimates, other publicly available information. The overall low to high Price / 2023E EPS multiples observed for the Spirit selected companies were 8.5x to 12.4x (with a median of 9.4x). The overall low to high Firm Value / 2023E EBITDAR multiples observed for the Spirit selected companies were 3.5x to 5.4x (with a median of 4.7x).

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Based on its professional judgment and experience, and taking into consideration the observed multiples for the Spirit selected companies, Citi identified selected illustrative ranges of multiples of (i) Price / 2023E EPS of 8.4x to 10.4x and (ii) Firm Value / 2023E EBITDAR of 4.2x to 5.2x. To derive approximate implied per share equity value reference ranges for Spirit, Citi (i) applied the range of Price / 2023E EPS multiples to Spirit’s estimated EPS for calendar year 2023, as provided in the Spirit Management Projections, and (ii) applied the range of Firm Value / 2023E EBITDAR multiples to Spirit’s estimated EBITDAR for calendar year 2023, as provided in the Spirit Management Projections, subtracted from the resulting approximate implied firm value reference range Spirit’s net debt as of December 31, 2021 (calculated as debt including the value of Spirit’s out of the money convertible notes, plus operating lease liabilities, less cash and cash equivalents), and divided the results by diluted share counts of Spirit calculated using the treasury stock method, based on equity information as of February 4, 2022 as provided by Spirit management. This analysis indicated the following approximate implied per share equity value reference ranges for Spirit, as compared to the closing share price of the Spirit common stock, as of February 4, 2022, of $21.73, and the implied per share value of the merger consideration of $25.83:

Frontier

Citi reviewed certain publicly available financial and stock market information of Frontier and the following selected companies (which we refer to as the “Frontier selected companies”).

Although none of the Frontier selected companies listed above is directly comparable to Frontier, the companies included were chosen because they have operations that, for purposes of Citi’s analysis and based on its experience and professional judgment, may be considered generally relevant in evaluating those of Frontier based on business sector participation, operational characteristics and financial metrics. The quantitative information used in this analysis, to the extent that it is based on market data, was based on market data as of February 4, 2022.

For each of the Frontier selected companies, and for Frontier for reference, Citi calculated and reviewed, among other information, (i) P / 2023E EPS multiples; and (ii) Firm Value / 2023E EBITDAR multiples. Financial data of the Frontier selected companies were based on Wall Street research analysts’ estimates and other publicly available information. With respect to the multiples calculated for Frontier for reference, the financial data of Frontier was based on Wall Street research analysts’ estimates, other publicly available information. The overall low to high Price / 2023E EPS multiples observed for the selected companies were 8.2x to 12.4x (with a median of 9.4x). The overall low to high Firm Value / 2023E EBITDAR multiples observed for the selected companies were 3.5x to 5.4x (with a median of 4.7x).

Based on its professional judgment and experience, and taking into consideration the observed multiples for the Frontier selected companies, Citi identified selected illustrative ranges of multiples of (i) Price / 2023E EPS of 8.4 to 10.4x and (ii) Firm Value / 2023E EBITDAR of 4.2x to 5.2x. To derive approximate implied per share equity value reference ranges for Frontier, Citi (i) applied the range of Price / 2023E EPS multiples to Frontier’s

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estimated EPS for calendar year 2023, as provided in the Frontier Management Projections and (ii) applied the range of Firm Value / 2023E EBITDAR multiples to Frontier’s estimated EBITDAR for calendar year 2023, as provided in the Frontier Management Projections, subtracted from the resulting approximate implied firm value reference range Frontier’s net debt as of December 31, 2021 (calculated as debt, plus operating lease liabilities less cash), and divided the results by diluted share counts of Frontier calculated using the treasury stock method, based on equity information as of February 4, 2022 as provided by Frontier management. This analysis indicated the following approximate implied per share equity value reference ranges for Frontier, as compared to the closing share price of the Frontier common stock, as of February 4, 2022, of $12.39:

Present Value of Future Share Price Analyses

Citi performed separate present value of future share price analyses of Spirit and Frontier, in each case, on a standalone basis.

Spirit

Citi performed an analysis to derive a range of illustrative present values per share of Spirit common stock as of February 4, 2022 based on theoretical future prices calculated by Citi for the shares of Spirit common stock based on the Spirit Management Projections. Citi derived a range of theoretical future values per share for the shares of Spirit common stock as of December 31 of each of 2022, 2023 and 2024 based on the Spirit Management Projections. Citi derived this range of theoretical future values per share by applying illustrative one year forward price to adjusted EPS multiples of 8.2x to 11.1x to estimates of the adjusted EPS of Spirit for each of calendar years 2023, 2024 and 2025, as reflected in the Spirit Management Projections. The price to adjusted EPS multiples used by Citi were derived based on Citi’s professional judgment and experience and taking into account Spirit’s Price / 2023E EPS multiple based on Wall Street research analysts’ estimates and other publicly available information as of February 4, 2022 and historical price to adjusted EPS multiples of the Frontier selected companies during the five year period ended on February 21, 2020. By applying a discount rate of 14.3%, reflecting a mid-point estimate of Spirit’s cost of equity, Citi discounted to present value as of February 4, 2022 the theoretical future values per share it derived for Spirit as described above, to yield a range of illustrative present values per share of Spirit common stock. This analysis indicated an approximate implied per share equity value reference range for Spirit of $28.65 to $47.15, as compared to the closing share price of the Spirit common stock as of February 4, 2022, of $21.73, and the implied per share value of the merger consideration, of $25.83.

Frontier

Citi performed an analysis to derive a range of illustrative present values per share of Frontier common stock as of February 4, 2022 based on theoretical future prices calculated by Citi for the shares of Frontier common stock based on the Frontier Management Projections. Citi derived a range of theoretical future values per share for the shares of Frontier common stock as of December 31 of each of 2022, 2023 and 2024 based on the Frontier Management Projections. Citi derived this range of theoretical future values per share by applying illustrative one year forward price to adjusted EPS multiples of 8.6x to 11.1x to estimates of the adjusted EPS of Frontier for each of calendar years 2023, 2024 and 2025, as reflected in the Frontier Management Projections. The price to adjusted EPS multiples used by Citi were derived based on Citi’s professional judgment and experience and taking into account Frontier’s Price / 2023E EPS multiple based on Wall Street research analysts’ estimates and other publicly available information as of February 4, 2022, and historical price to adjusted EPS multiples of the Frontier selected companies during the five year period ended on February 21, 2020. By applying a discount rate

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of 14.3%, reflecting a mid-point estimate of Frontier’s cost of equity, Citi discounted to present value as of February 4, 2022 the theoretical future values per share it derived for Frontier as described above, to yield a range of illustrative present values per share of Frontier common stock. This analysis indicated an approximate implied per share equity value reference range for Frontier of $11.90 to $18.55, as compared to the closing share price of the Frontier common stock, as of February 4, 2022, of $12.39.

Implied Exchange Ratio Analysis

Utilizing the approximate implied per share equity value reference ranges derived for Spirit based on the discounted cash flow, selected public companies and present value of future share price analyses above, compared in each case to the approximate implied per share equity value reference ranges derived for Frontier based on the discounted cash flow, selected public companies and present value of future share price analyses described above, Citi calculated the following approximate implied exchange ratio reference ranges, as compared to the exchange ratio pursuant to the merger agreement of 1.9126x, after taking into account the cash consideration to be paid by Frontier pursuant to the merger agreement:

Illustrative Value Creation Analysis—Discounted Cash Flow

Citi performed an illustrative value creation analysis in which Citi observed the impact of the proposed merger on the equity value of shares of Frontier common stock owned by Frontier stockholders by calculating and comparing illustrative per share equity values for Frontier on a standalone basis and Frontier on a pro forma basis, giving effect to the consummation of the proposed merger. Citi derived an implied equity value for Frontier on a pro forma basis, giving effect to the consummation of the proposed merger, by calculating the sum of (i) the midpoint of implied equity values for Frontier derived pursuant to the “Discounted Cash Flow Analysis—Frontier” described above, plus (ii) the midpoint of implied equity values for Spirit derived pursuant to the “Discounted Cash Flow Analysis—Spirit”, less (iii) the aggregate amount of cash consideration to be paid to Spirit stockholders pursuant to the merger agreement, less (iv) estimated transaction expenses, as provided by Frontier management, plus (v) the midpoint estimated present value of the expected Synergies. With respect to Frontier on a standalone basis, Citi divided the implied equity values by the total number of fully diluted shares outstanding of Frontier calculated using information provided by Frontier management, to derive approximate implied per share equity values for Frontier on a standalone basis. With respect to Frontier on a pro forma basis, giving effect to the consummation of the proposed merger, Citi divided the resulting equity values by the total number of fully diluted shares outstanding of Frontier on a pro forma basis, giving effect to the consummation of the proposed merger including the shares to be issued to Spirit stockholders pursuant to the merger agreement, calculated using information provided by Frontier management, to derive approximate implied per share equity values for Frontier on a pro forma basis, giving effect to the consummation of the proposed merger. This analysis indicated illustrative value creation to the holders of Frontier common stock of 35% with Synergies, and 7% without Synergies.

Illustrative Value Creation Analysis—Pro Forma Future Share Price

Citi performed an illustrative value creation analysis in which Citi observed the impact of the proposed merger on the equity value of shares of Frontier common stock owned by Frontier stockholders by calculating and comparing illustrative theoretical future prices for the shares of Frontier common stock on a standalone basis and

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Frontier on a pro forma basis, giving effect to the consummation of the proposed merger. Citi derived a range of theoretical future values per share for the shares of Frontier common stock, on a standalone basis and on a pro forma basis, giving effect to the consummation of the proposed merger including Synergies, as of December 31 of each of 2022, 2023 and 2024 by applying illustrative one year forward price to adjusted EPS multiple of 8.6x (reflecting Frontier’s 2023 EPS multiple based on Wall Street research analysts’ consensus estimates) to estimates of the adjusted EPS of Frontier on a standalone basis and a pro forma basis for each of calendar years 2023, 2024 and 2025, as reflected in the Frontier Management Projections. This analysis indicated illustrative value creation to the holders of Frontier common stock of 20% in 2022, 27% in 2023 and 42% in 2024.

Certain Additional Information

Citi observed certain other information with respect to Spirit and Frontier that was not considered part of its financial analyses with respect to its opinion, but was noted for reference purposes only, including the following:

52–Week Trading Range

Citi reviewed the historical intra-day share prices of the Spirit common stock for the 52-week period ended February 4, 2022 and the Frontier common stock for the period from April 1, 2021 (the date of Frontier’s initial public offering) through February 4, 2022. Citi noted that the low and high intraday prices of the Spirit common stock during this period were approximately $19.40 and $40.77 per share, and that the low and high intraday prices of the Frontier common stock during this period were approximately $11.73 and $22.70 per share.

Equity Research Analyst Price Targets

Citi reviewed the most recent publicly available research analysts’ one-year forward price targets for the Spirit common stock and Frontier common stock prepared and published by selected research analysts. Citi noted that as of February 4, 2022 such price targets ranged from $23.00 to $43.00 for the Spirit common stock and $18.00 to $25.00 for the Frontier common stock. Citi also noted that these ranges of price targets, discounted one year at an estimated 14.3% cost of equity for both Spirit and Frontier, was $20.10 to $37.60 for the Spirit common stock and $15.75 to $21.90 for the Frontier common stock.

Premia Paid

Citi calculated, using publicly available information, the median one-day unaffected stock price premia paid for acquisition transactions announced during the period from January 1, 2010 through January 31, 2022 involving 100% stock consideration with a transaction value between $1 billion to $10 billion that Citi deemed appropriate in its professional judgment, which indicated a median one-day unaffected stock price premium of 14.9%. Based on the foregoing review and its professional judgment and experience, Citi applied a premia reference range of 4.9% to 24.9% to the closing share price of shares of Spirit common stock on February 4, 2022 of $21.73. This analysis indicated an approximate implied per share equity value reference range for Spirit of $22.80 to $27.15.

Miscellaneous

Frontier has agreed to pay Citi for its services in connection with the merger an aggregate fee of $20 million, of which $3 million was payable in connection with the delivery of Citi’s opinion to the Frontier board and the remainder is payable contingent upon consummation of the merger, and an additional discretionary fee of $1.5 million payable at the discretion of Frontier upon consummation of the merger. In addition, Frontier agreed to reimburse Citi for Citi’s expenses, including fees and expenses of counsel, and to indemnify Citi and related parties against certain liabilities, including liabilities under federal securities laws, arising out of Citi’s engagement.

As the Frontier board was aware, Citi and its affiliates in the past have provided, currently are providing and/or in the future may provide, certain investment banking, commercial banking and other financial services to

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Frontier unrelated to the proposed merger, for which services Citi and such affiliates have received and expect to receive compensation, including, without limitation, during the two year period prior to the date of Citi’s opinion, having acted as lead left bookrunner in connection with Frontier’s initial public offering, as facility agent, arranger, and lender in connection with an amendment to a certain pre-delivery payment facility of Frontier and as a lender in connection with certain loans of Frontier. For the services described above for Frontier, Citi and its affiliates received, during the two year period prior to the date of Citi’s opinion, aggregate fees of approximately $6.1 million from Frontier and/or certain of its affiliates. In addition, as the Frontier board was also aware, Citi and its affiliates in the past have provided, currently are providing and in the future may provide, certain investment banking, commercial banking and other financial services to Indigo Fund and/or its affiliates and portfolio companies (which we refer to as the “Indigo Group”), the controlling shareholder of Frontier, unrelated to the proposed Merger and excluded from the services provided to Frontier, for which services Citi and such affiliates have received and expect to receive compensation, including, without limitation, during the two year period prior to the date hereof, having acted or acting as financial advisor in connection with certain M&A related activity and as bookrunner in connection with certain equity offerings of the Indigo Group. For the services described above for the Indigo Group, Citi and its affiliates received, during the two year period prior to the date of Citi’s opinion, aggregate fees of approximately $0.9 million from the Indigo Group and/or certain of its affiliates. Citi and its affiliates in the past have provided, currently are providing and in the future may provide, certain investment banking, commercial banking and other financial services to Spirit, unrelated to the proposed merger, for which services Citi and such affiliates have received and expect to receive compensation, including, without limitation, during the two year period prior to the date of Citi’s opinion, having acted or acting as bookrunner in connection with certain equity offerings of Spirit, including Spirit’s convertible senior notes, as a bookrunner in connection with certain credit facilities of Spirit and as lender in connection with certain loans of Spirit. For the services described above for Spirit, Citi and its affiliates received, during the two year period prior to the date of Citi’s opinion, aggregate fees of approximately $10.7 million from Spirit and/or certain of its affiliates. In the ordinary course of Citi’s business, Citi and its affiliates may actively trade or hold the securities of Frontier, affiliates of the Indigo Group and Spirit for Citi’s own account or for the account of its customers and, accordingly, may at any time hold a long or short position in such securities. In addition, Citi and its affiliates (including Citigroup Inc. and its affiliates) may maintain relationships with Frontier, the Indigo Group, Spirit and their respective affiliates.

Frontier selected Citi to act as financial advisor in connection with the merger based on Citi’s reputation, experience and familiarity with Frontier, Spirit and their respective businesses. Citi is an internationally recognized investment banking firm that regularly engages in the valuation of businesses and their securities in connection with mergers and acquisitions, negotiated underwritings, competitive bids, secondary distributions of listed and unlisted securities, private placements and valuations for estate, corporate and other purposes.

Spirit’s Reasons for the Merger; Recommendation of the Spirit Board of Directors

In reaching its decision to approve the merger agreement and recommend its adoption by Spirit’s stockholders, the Spirit board of directors consulted with management as well as Spirit’s financial and legal advisers, and also considered a variety of factors that the Spirit board of directors viewed as supporting its decision, including, without limitation, the following:

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The Spirit board of directors also considered the potential adverse impact of other factors weighing against its decision to approve the merger agreement and recommend its adoption by Spirit’s stockholders, including, without limitation, the following:

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In addition, the Spirit board of directors also realized that there can be no assurance regarding future results, including results expected or considered in the factors listed above. However, the Spirit board of directors concluded that the potential positive factors outweighed the risks and other potentially negative factors associated with the merger.

In reaching its conclusion, the Spirit board of directors did not find it practical to assign, and did not assign, any relative or specific weight to the different factors that were considered, and individual members of the Spirit board of directors may have given different weight to different factors. It should be noted that the explanation of the reasoning of the Spirit board of directors and certain information presented in this section are forward-looking in nature and should be read in light of the factors set forth in the section entitled “Cautionary Statement Regarding Forward-Looking Statements.”

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Opinion of Barclays Capital Inc.

Spirit engaged Barclays to act as its financial advisor with respect to pursuing strategic alternatives for Spirit, including a possible sale of Spirit, pursuant to an engagement letter dated November 21, 2019. On February 5, 2022, Barclays rendered its oral opinion (which was subsequently confirmed in writing) to Spirit’s board of directors that, as of such date and based upon and subject to the qualifications, limitations and assumptions stated in its opinion, the consideration to be received by the stockholders of Spirit in the merger is fair, from a financial point of view, to such stockholders.

The full text of Barclays’ written opinion, dated as of February 5, 2022, is attached as Annex C to this information statement and proxy statement/prospectus. Barclays’ written opinion sets forth, among other things, the assumptions made, procedures followed, factors considered and limitations upon the review undertaken by Barclays in rendering its opinion. You are encouraged to read the opinion carefully in its entirety. The following is a summary of Barclays’ opinion and the methodology that Barclays used to render its opinion. This summary is qualified in its entirety by reference to the full text of the opinion.

Barclays’ opinion, the issuance of which was approved by Barclays’ Fairness Opinion Committee, is addressed to the board of directors of Spirit, addresses only the fairness, from a financial point of view, of the consideration to be received by the stockholders of Spirit in the proposed transaction and does not constitute a recommendation to any stockholder of Spirit as to how such stockholder should vote with respect to the proposed transaction or any other matter. The terms of the proposed transaction were determined through arm’s-length negotiations between Spirit and Frontier and were unanimously approved by Spirit’s board of directors. Barclays did not recommend any specific form of consideration to Spirit or that any specific form of consideration constituted the only appropriate consideration for the proposed transaction. Barclays was not requested to address, and its opinion does not in any manner address, Spirit’s underlying business decision to proceed with or effect the proposed transaction, the likelihood of the consummation of the proposed transaction, or the relative merits of the proposed transaction as compared to any other transaction in which Spirit may engage. In addition, Barclays expressed no opinion on, and its opinion does not in any manner address, the fairness of the amount or the nature of any compensation to any officers, directors or employees of any parties to the proposed transaction, or any class of such persons, relative to the consideration to be offered to the stockholders of Spirit in the proposed transaction or otherwise. No limitations were imposed by Spirit’s board of directors upon Barclays with respect to the investigations made or procedures followed by it in rendering its opinion.

In arriving at its opinion, Barclays, among other things:

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In arriving at its opinion, Barclays assumed and relied upon the accuracy and completeness of the financial and other information used by Barclays without any independent verification of such information (and had not assumed responsibility or liability for any independent verification of such information). Barclays also relied upon the assurances of the management of Spirit that they were not aware of any facts or circumstances that would make such information inaccurate or misleading. With respect to Spirit Projections, upon the advice of Spirit, Barclays assumed that such projections were reasonably prepared on a basis reflecting the best currently available estimates and judgments of the management of Spirit as to the future financial performance of Spirit and that Spirit would perform substantially in accordance with such projections. With respect to the Frontier Projections, upon the advice of Spirit, Barclays assumed that such projections were reasonably prepared on a basis reflecting the best currently available estimates and judgments of the management of Frontier and Spirit as to the future financial performance of Frontier and that Frontier would perform substantially in accordance with such projections. Furthermore, upon the advice of Spirit, Barclays assumed that the Expected Synergies reflect the best currently available estimates and judgments of the management of Frontier and Spirit as to their amounts and timing and would be realized in accordance with such estimates. Barclays assumed no responsibility for and expressed no view as to any such projections or estimates or the assumptions on which they were based. In arriving at its opinion, Barclays did not conduct a physical inspection of the properties and facilities of Spirit or Frontier and did not make or obtain any evaluations or appraisals of the assets or liabilities of Spirit or Frontier. Barclays’ opinion was necessarily based upon market, economic and other conditions as they existed on, and could be evaluated as of, February 5, 2022. Barclays assumed no responsibility for updating or revising its opinion based on events or circumstances that may occur after February 5, 2022. Barclays expressed no opinion as to the prices at which (i) Spirit common stock or Frontier common stock would trade following the announcement of the proposed transaction or (ii) the Frontier common stock would trade at any time following the consummation of the proposed transaction.

Barclays assumed that the executed merger agreement will conform in all material respects to the last draft reviewed by Barclays. In addition, Barclays assumed the accuracy of the representations and warranties contained in the merger agreement and all agreements related thereto. Barclays also assumed, upon the advice of Spirit, that all material governmental, regulatory and third party approvals, consents and releases for the proposed transaction will be obtained within the constraints contemplated by the merger agreement and that the proposed transaction will be consummated in accordance with the terms of the merger agreement without waiver, modification or amendment of any material term, condition or agreement thereof. Barclays did not express any opinion as to any tax or other consequences that might result from the proposed transaction, nor did Barclays’ opinion address any legal, tax, regulatory or accounting matters, as to which Barclays understood Spirit had obtained such advice as it deemed necessary from qualified professionals.

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In connection with rendering its opinion, Barclays performed certain financial, comparative and other analyses as summarized below. In arriving at its opinion, Barclays did not ascribe a specific range of values to the shares of Spirit common stock but rather made its determination as to fairness, from a financial point of view, of the consideration to be received by the stockholders of Spirit in the proposed transaction on the basis of various financial and comparative analyses. The preparation of a fairness opinion is a complex process and involves various determinations as to the most appropriate and relevant methods of financial and comparative analyses and the application of those methods to the particular circumstances. Therefore, a fairness opinion is not readily susceptible to summary description.

In arriving at its opinion, Barclays did not attribute any particular weight to any single analysis or factor considered by it but rather made qualitative judgments as to the significance and relevance of each analysis and factor relative to all other analyses and factors performed and considered by it and in the context of the circumstances of the particular transaction. Accordingly, Barclays believes that its analyses must be considered as a whole, as considering any portion of such analyses and factors, without considering all analyses and factors as a whole, could create a misleading or incomplete view of the process underlying its opinion.

Summary of Material Financial Analyses

The following is a summary of the material financial analyses used by Barclays in preparing its opinion to Spirit’s board of directors. The summary of Barclays’ analyses and reviews provided below is not a complete description of the analyses and reviews underlying Barclays’ opinion. The preparation of a fairness opinion is a complex process involving various determinations as to the most appropriate and relevant methods of analysis and review and the application of those methods to particular circumstances, and, therefore, is not readily susceptible to summary description.

For the purposes of its analyses and reviews, Barclays made numerous assumptions with respect to industry performance, general business, economic, market and financial conditions and other matters, many of which are beyond the control of Spirit, Frontier, Barclays or any other parties to the proposed transaction. No company, business or transaction considered in Barclays’ analyses and reviews is identical to Spirit, Frontier, Merger Sub or the proposed transaction, and an evaluation of the results of those analyses and reviews is not entirely mathematical. Rather, the analyses and reviews involve complex considerations and judgments concerning financial and operating characteristics and other factors that could affect the acquisition, public trading or other values of the companies, businesses or transactions considered in Barclays’ analyses and reviews. None of Spirit, Frontier, Merger Sub, Barclays or any other person assumes responsibility if future results are materially different from those discussed. Any estimates contained in these analyses and reviews and the ranges of valuations resulting from any particular analysis or review are not necessarily indicative of actual values or predictive of future results or values, which may be significantly more or less favorable than as set forth below. In addition, analyses relating to the value of companies, businesses or securities do not purport to be appraisals or reflect the prices at which the companies, businesses or securities may actually be sold. Accordingly, the estimates used in, and the results derived from, Barclays’ analyses and reviews are inherently subject to substantial uncertainty.

The summary of the financial analyses and reviews provided below includes information presented in tabular format. In order to fully understand the financial analyses and reviews used by Barclays, the tables must be read together with the text of each summary, as the tables alone do not constitute a complete description of the financial analyses and reviews. Considering the data in the tables below without considering the full description of the analyses and reviews, including the methodologies and assumptions underlying the analyses and reviews, could create a misleading or incomplete view of Barclays’ analyses and reviews.

Selected Comparable Company Analysis

In order to assess how the public market values shares of similar publicly traded companies and to provide a range of relative implied equity values per share of Spirit and per share of Frontier by reference to those

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companies, which could then be used to calculate implied exchange ratio ranges, Barclays reviewed and compared specific financial and operating data relating to Spirit and Frontier, respectively, with selected companies that Barclays, based on its experience in the airline industry, deemed comparable to Spirit and Frontier, respectively. The selected comparable companies with respect to Spirit were:

The selected comparable companies with respect to Frontier were:

Barclays calculated and compared various financial multiples and ratios of Spirit and Frontier and the selected comparable companies. As part of its selected comparable company analysis, Barclays calculated and analyzed each company’s ratio of its current stock price to its projected earnings per share (commonly referred to as a price earnings ratio, or P/E), and each company’s adjusted enterprise value to certain projected financial criteria (such as revenue, earnings before interest, taxes, depreciation and amortization and rent, or EBITDAR). The adjusted enterprise value of each company was obtained by adding its short and long-term debt and operating leases to the sum of the market value of its common equity, the value of any preferred stock (at liquidation value) and the book value of any minority interest, and subtracting its cash and cash equivalents. All of these calculations were performed, and based on publicly available financial data and closing prices, as of February 4, 2022, the last trading date prior to the delivery of Barclays’ opinion. The results of this selected comparable company analysis are summarized below:

Barclays selected the comparable companies listed above because their businesses and operating profiles are reasonably similar to that of Spirit or Frontier, as applicable. However, because of the inherent differences between the business, operations and prospects of Spirit or Frontier, as applicable and those of the selected comparable companies, Barclays believed that it was inappropriate to, and therefore did not, rely solely on the quantitative results of the selected comparable company analysis. Accordingly, Barclays also made qualitative judgments concerning differences between the business, financial and operating characteristics and prospects of Spirit or Frontier, as applicable and the selected comparable companies that could affect the public trading values of each in order to provide a context in which to consider the results of the quantitative analysis. These qualitative judgments related primarily to the differing sizes, growth prospects, profitability levels and degree of operational risk between Spirit or Frontier, as applicable and the companies included in the selected company analysis. Due to the impact of the COVID-19 pandemic on the air transportation services industry, Barclays focused its analysis of the selected financial metrics to 2023E.

Spirit Standalone Valuation. Based upon the analysis described above and its professional judgment, Barclays selected a range of 2023 estimated P/E multiples of 8.0x to 10.0x for Spirit and applied such range to Spirit’s

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adjusted EPS, as set out in the Spirit Projections, to calculate a range of implied prices per share of Spirit common stock of $31 to $39. Based upon its professional judgments, Barclays also selected a range of 2023 estimated EBITDAR multiples of 4.0x to 5.0x for Spirit and applied such range to Spirit’s EBITDAR, as set out in the Spirit Projections, to calculate a range of implied prices per share of Spirit common stock of $18 to $31. Barclays noted that the implied per share merger consideration (as described below) of $25.83 was below the 2023 estimated P/E range and within the 2023 estimated EBITDAR range.

Frontier Standalone Valuation. Based upon the analysis described above and its professional judgment, Barclays selected a range of 2023 estimated P/E multiples of 8.0x to 10.0x for Frontier and applied such range to Frontier’s adjusted EPS, as set out in the Frontier Projections, to calculate a range of implied prices per share of Frontier common stock of $12 to $16. Based upon its professional judgments, Barclays also selected a range of 2023 estimated EBITDAR multiples of 4.0x to 5.0x for Spirit and applied such range to Frontier’s EBITDAR, as set out in the Frontier Projections, to calculate a range of implied prices per share of Frontier common stock of $12 to $17.

For purposes of its opinion, Barclays calculated the implied value, as of February 4, 2022, of the proposed transaction consideration per Spirit common share to be $25.83 (the “implied per share merger consideration”), which was determined by adding the cash portion of the proposed transaction consideration of $2.13 per Spirit common share to $23.70, the implied value of the stock portion of the proposed transaction consideration per Spirit common share, which was derived by multiplying the closing price of $12.39 per share of Frontier common stock on February 4, 2022, the last trading day prior to the announcement of the proposed transaction, by the exchange ratio of 1.9126 shares of Frontier common stock per Spirit common share.

Discounted Cash Flow Analysis

In order to estimate the present value of the Spirit common stock and Frontier common stock, Barclays performed a discounted cash flow analysis of Spirit and Frontier. A discounted cash flow analysis is a traditional valuation methodology used to derive a valuation of an asset by calculating the “present value” of estimated future cash flows of the asset. “Present value” refers to the current value of future cash flows or amounts and is obtained by discounting those future cash flows or amounts by a discount rate that takes into account macroeconomic assumptions and estimates of risk, the opportunity cost of capital, expected returns and other appropriate factors.

Spirit Standalone Valuation. To calculate the estimated enterprise value of Spirit using the discounted cash flow method, Barclays (i) added Spirit’s projected after-tax unlevered free cash flows for fiscal years 2022 through 2026 based on the Spirit Projections to the “terminal value” of Spirit as of December 31, 2026 and then (ii) discounted such amount to its present value using a range of selected discount rates. The after-tax unlevered free cash flows were calculated by taking the projected total EBITDAR, adjusted for one-time or non-recurring items (“Adj. EBITDAR”), and subtracting rent expenses, unlevered cash taxes and capital expenditures and adjusting for the impact of depreciation and amortization, changes in working capital (including changes in deferred heavy maintenance) and certain other non-cash expenses. The residual value of Spirit at the end of the forecast period, or “terminal value,” was estimated by selecting a range of terminal value multiples based on estimated last twelve months EBITDAR (“LTM EBITDAR”) for the five year period ending December 31, 2026 of 5.5x to 7.5x, which was derived by analyzing historical average LTM EBITDAR multiples from selected comparable companies and applying such range to the Spirit Projections. The range of after-tax discount rates of 9.0% to 11.0% was selected based on an analysis of the weighted average cost of capital of Spirit and the comparable companies. Barclays then calculated a range of implied prices per share of Spirit by (A) (i) subtracting estimated total debt and (ii) adding cash, each as of December 31, 2021, from the estimated enterprise value using the discounted cash flow method and (B) dividing such amount by the fully diluted number of shares of Spirit common stock. These calculations resulted in a range of implied price per share of $34 to $64 (the “Spirit DCF Range”). Barclays noted that the implied per share merger consideration of $25.83 was below the Spirit DCF Range.

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Frontier Standalone Valuation. To calculate the estimated enterprise value of Frontier using the discounted cash flow method, Barclays (i) added Frontier’s projected after-tax unlevered free cash flows for fiscal years 2022 through 2026 based on the Frontier Projections to the “terminal value” of Frontier as of December 31, 2026 and then (ii) discounted such amount to its present value using a range of selected discount rates. The after-tax unlevered free cash flows were calculated by taking the projected total Adj. EBITDAR and subtracting rent expenses, unlevered cash taxes and capital expenditures and adjusting for the impact of depreciation and amortization, changes in working capital (including changes in deferred heavy maintenance), the net cash proceeds from sale-leaseback transactions (proceeds from sale-leaseback transactions less gains recognized on sale-leaseback transactions) and certain other non-cash expenses. The residual value of Frontier at the end of the forecast period, or “terminal value,” was estimated by selecting a range of terminal value multiples based on estimated LTM EBITDAR for the five year period ending December 31, 2026 of 5.5x to 7.5x, which was derived by analyzing historical average LTM EBITDAR multiples from selected comparable companies and applying such range to the Frontier Projections. The range of after-tax discount rates of 9.0% to 11.0% was selected based on an analysis of the weighted average cost of capital of Frontier and the comparable companies. Barclays then calculated a range of implied prices per share of Frontier by (A) (i) subtracting estimated total debt and (ii) adding cash, each as of December 31, 2021, from the estimated enterprise value using the discounted cash flow method and (B) dividing such amount by the fully diluted number of shares of Frontier common stock. These calculations resulted in a range of implied price per share of $23 to $37.

Implied Exchange Ratio Analysis

Using the implied value per share reference ranges for Spirit common stock and Frontier common stock indicated in the selected comparable company analysis and the discounted cash flow analysis of Spirit and Frontier described above, Barclays calculated cash adjusted ranges of implied exchange ratios of Spirit common stock into Frontier common stock, after taking into account the $2.13 cash consideration to be received in the merger. The following summarizes the result of these calculations, compared to the 1.9126x exchange ratio to be paid by Frontier in the merger:

Other Factors

Barclays also reviewed and considered other factors, which were not considered part of its financial analyses in connection with rendering its advice, but were references for informational purposes, including, among other things, the Historical Share Price Analysis and the Research Analyst Price Targets Analysis described below.

Historical Share Price Analysis

To illustrate the trend in the historical trading prices of Spirit common stock, Barclays considered historical data with regard to the trading prices of Spirit common stock for the period beginning on the Frontier IPO Date and ending February 4, 2022 and compared such data with the relative stock price performances during the same periods of Frontier, the S&P 500 and the selected companies listed under the caption “Selected Comparable Company Analysis” above. Barclays noted that the closing price of Spirit common stock ranged from $20 to $40 during the 52-week period ended February 4, 2022, compared to Frontier which ranged from $12 to $22 during the period beginning on the Frontier IPO Date and ended February 4, 2022. The implied cash adjusted exchange ratio of Spirit common stock into Frontier common stock from this analysis ranged from 0.817x to 3.050x.

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Research Analyst Price Targets

Barclays reviewed, for informational purposes, as of February 4, 2022, the publicly available price targets of Spirit and Frontier common stock published by equity research analysts associated with various Wall Street bulge-bracket and middle market brokers. The research analysts’ price target per share of Spirit common stock ranged from $25 to $43 per share compared to Frontier common stock which ranged from $18 to $25 per share. The publicly available share price targets published by such equity research analysts do not necessarily reflect the current market trading price for Spirit common stock or Frontier common stock and these estimates are subject to uncertainties, including future financial performance of Spirit and Frontier and future market conditions. The implied cash adjusted exchange ratio of Spirit common stock into Frontier common stock based on these targets ranged from 0.915x to 2.271x. Research analyst price targets for Spirit and Frontier were used for informational purposes only and were not included in Barclays’ financial analyses.

General

Barclays is an internationally recognized investment banking firm and, as part of its investment banking activities, is regularly engaged in the valuation of businesses and their securities in connection with mergers and acquisitions, investments for passive and control purposes, negotiated underwritings, competitive bids, secondary distributions of listed and unlisted securities, private placements and valuations for estate, corporate and other purposes. Spirit’s board of directors selected Barclays because of its familiarity with Spirit and its qualifications, reputation and experience in the valuation of businesses and securities in connection with mergers and acquisitions generally, as well as substantial experience in transactions comparable to the proposed transaction.

Barclays is acting as financial advisor to Spirit in connection with the proposed transaction. As compensation for its services in connection with the proposed transaction, Spirit paid Barclays a fee of $3 million upon the delivery of Barclays’ opinion (which we refer to as the “Opinion Fee”). The Opinion Fee was not contingent upon the conclusion of Barclays’ opinion or the consummation of the proposed transaction. Additional compensation of $16 million will be payable on completion of the proposed transaction against which the amounts paid for the opinion will be credited. In addition, Spirit has agreed to reimburse Barclays for a portion of its reasonable out-of-pocket expenses incurred in connection with the proposed transaction and to indemnify Barclays for certain liabilities that may arise out of its engagement by Spirit and the rendering of Barclays’ opinion. Barclays has performed various investment banking services for Spirit and Frontier in the past, and may perform such services in the future, and has received, and would expect to receive, customary fees for such services. Specifically, in the past two years, Barclays has performed the following investment banking and financial services: (i) having acted as a joint bookrunner on Frontier’s initial public offering in March 2021; (ii) having acted as an underwriter on Spirit’s 2025 convertible notes in May 2020; (iii) having acted as an underwriter on Spirit’s $175 million follow on equity offering in May 2020; (iv) having acted as a financial advisor to Spirit in connection with the Coronavirus Aid, Relief, and Economic Security Act of 2020; (v) having acted as a structuring agent and joint bookrunner on Spirit’s $850 million senior secured notes in September 2020; (vi) having acted as an underwriter on Spirit’s 2026 convertible notes in April 2021; (vii) having acted as an advisor on Spirit’s registered direct offering and repurchase in April 2021; (viii) having served as a lender under Spirit’s existing revolving credit facility; (ix) having served as a lender under Frontier’s pre-delivery deposit payments financing facility; and (x) having provided advisory services to Spirit on its assessment of certain strategic alternatives. During the period beginning January 1, 2020 through the date of rendering its opinion, the aggregate amount of fees that Barclays received from Spirit and Frontier for the investment banking and financial services described above was approximately $12.6 million and $5.5 million, respectively.

Barclays, its subsidiaries and its affiliates engage in a wide range of businesses from investment and commercial banking, lending, asset management and other financial and non-financial services. In the ordinary course of Barclays’ business, Barclays and its affiliates may actively trade and effect transactions in the equity, debt and/or other securities (and any derivatives thereof) and financial instruments (including loans and other obligations) of Spirit and Frontier for its own account and for the accounts of its customers and, accordingly, may at any time hold long or short positions and investments in such securities and financial instruments.

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Opinion of Morgan Stanley & Co. LLC

Spirit retained Morgan Stanley to act as financial advisor to the Spirit board of directors in connection with the proposed merger, pursuant to an engagement letter dated December 17, 2019. The Spirit board of directors selected Morgan Stanley to act as its financial advisor based on Morgan Stanley’s qualifications, expertise and reputation, its knowledge of, and involvement in, recent transactions in the industry, and its knowledge of Spirit’s business and affairs. At the meeting of the Spirit board of directors on February 5, 2022, Morgan Stanley rendered its oral opinion, subsequently confirmed in writing, that as of such date, and based upon and subject to the various assumptions made, procedures followed, matters considered and qualifications and limitations on the scope of the review undertaken by Morgan Stanley as set forth in the written opinion, the merger consideration to be received by the holders of shares of Spirit common stock (other than certain excluded shares) pursuant to the merger agreement was fair from a financial point of view to such holders of shares of Spirit common stock.

The full text of the written opinion of Morgan Stanley, dated as of February 5, 2022, which sets forth, among other things, the various assumptions made, procedures followed, matters considered and qualifications and limitations on the scope of the review undertaken by Morgan Stanley in rendering its opinion, is attached to this information statement and proxy statement/prospectus as Annex D. You are encouraged to read the opinion carefully and in its entirety. Morgan Stanley’s opinion was rendered for the benefit of the Spirit board of directors, in its capacity as such, and addressed only the fairness from a financial point of view, as of the date of such opinion, of the merger consideration to the holders of shares of Spirit common stock (other than the certain excluded shares). Morgan Stanley’s opinion did not address any other aspects or implications of the merger, including the relative merits of the merger as compared to any other alternative business transaction, or other alternatives, the prices at which shares of Frontier common stock or Spirit common stock would trade following consummation of the merger or at any time, or the fairness of the amount or nature of the compensation to any officers, directors or employees of Spirit, or any class of such persons, relative to the merger consideration to be received by the holders of shares of Spirit common stock pursuant to the merger. Morgan Stanley did not express any opinion or recommendation as to how the stockholders of Spirit should vote at the stockholders’ meeting to be held in connection with the merger. The summary of the opinion of Morgan Stanley set forth below is qualified in its entirety by reference to the full text of the opinion.

In connection with rendering its opinion, Morgan Stanley, among other things:

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In arriving at its opinion, Morgan Stanley assumed and relied upon, without independent verification, the accuracy and completeness of the information that was publicly available or supplied or otherwise made available to Morgan Stanley by Spirit and Frontier, and formed a substantial basis for its opinion. With respect to the financial projections, including information relating to certain strategic, financial and operational benefits anticipated from the merger, Morgan Stanley assumed that they had been reasonably prepared on bases reflecting the best currently available estimates and judgments of the respective managements of Spirit and Frontier of the future financial performance of Spirit and Frontier. In addition, Morgan Stanley assumed that the merger will be consummated in accordance with the terms set forth in the merger agreement without any waiver, amendment or delay of any terms or conditions, including, among other things, that the definitive merger agreement will not differ in any material respect from the draft thereof furnished to Morgan Stanley. Morgan Stanley assumed that in connection with the receipt of all the necessary governmental, regulatory or other approvals and consents required for the proposed merger, no delays, limitations, conditions or restrictions would be imposed that would have a material adverse effect on the contemplated benefits expected to be derived in the proposed merger. In arriving at its opinion, Morgan Stanley was not authorized to solicit, and did not solicit, interest from any party with respect to any acquisition, business combination or other extraordinary transaction involving Spirit. Morgan Stanley relied upon, without independent verification, the assessment by the managements of Spirit and Frontier of: (i) the strategic, financial and other benefits expected to result from the merger; (ii) the timing and risks associated with the integration of Spirit and Frontier; (iii) their ability to retain key employees of Spirit and Frontier, respectively and (iv) the validity of, and risks associated with, Spirit and Frontier’s existing and future technologies, intellectual property, products, services and business models. Morgan Stanley did not express any view on, and its opinion did not address, any other term or aspect of the merger agreement or the transactions contemplated thereby or any term or aspect of any other agreement or instrument contemplated by the merger agreement or entered into or amended in connection therewith. Morgan Stanley is not a legal, tax or regulatory advisor. Morgan Stanley is a financial advisor only and relied upon, without independent verification, the assessment of Frontier and Spirit and their legal, tax and regulatory advisors with respect to legal, tax and regulatory matters. Morgan Stanley expressed no opinion with respect to the fairness of the amount or nature of the compensation to any of Spirit’s officers, directors or employees, or any class of such persons, relative to the merger consideration to be received by the holders of shares of Spirit common stock (other than certain excluded shares) in the transaction. Morgan Stanley expressed no opinion with respect to the treatment of the Spirit convertible notes or the Spirit warrants pursuant to the merger agreement. Morgan Stanley did not make any independent valuation or appraisal of the assets or liabilities of Spirit or Frontier, nor was Morgan Stanley furnished with any such valuations or appraisals. Morgan Stanley’s opinion was necessarily based on financial, economic, market and other conditions as in effect on, and the information made available to Morgan Stanley as of, February 5, 2022. Events occurring after February 5, 2022 may affect Morgan Stanley’s opinion and the assumptions used in preparing it, and Morgan Stanley did not assume any obligation to update, revise or reaffirm its opinion.

Summary of Financial Analyses

The following is a summary of the material financial analyses performed by Morgan Stanley in connection with its oral opinion and the preparation of its written opinion dated February 5, 2022. The following summary is not a

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complete description of Morgan Stanley’s opinion or the financial analyses performed and factors considered by Morgan Stanley in connection with its opinion, nor does the order of analyses described represent the relative importance or weight given to those analyses. In connection with arriving at its opinion, Morgan Stanley considered all of its analyses as a whole and did not attribute any particular weight to any analysis described below. Considering any portion of such analyses and factors considered, without considering all analyses and factors, could create a misleading or incomplete view of the process underlying Morgan Stanley’s opinion. Some of these summaries of financial analyses include information presented in tabular format. In order to fully understand the financial analyses used by Morgan Stanley, the tables must be read together with the text of each summary. The tables alone do not constitute a complete description of the financial analyses. Furthermore, mathematical analysis (such as determining the average or median) is not in itself a meaningful method of using the data referred to below.

Except as otherwise noted, the following quantitative information, to the extent that it is based on market data, is based on market data as it existed on or before February 4, 2022, the last trading day prior to the date of the meeting of the Spirit board of directors at which Morgan Stanley rendered its oral opinion. Capitalization information for each of Spirit and Frontier, including fully-diluted number of shares and balance sheet information, were provided on February 4, 2022 by Spirit management and Frontier management, respectively, to Morgan Stanley, and were approved by Spirit management for Morgan Stanley’s use in its financial analyses. The various analyses summarized below were based on the closing price of $21.73 per Spirit share as of February 4, 2022 and the closing price of $12.39 per Frontier share as of February 4, 2022 and are not necessarily indicative of current market conditions.

In performing the financial analyses summarized below and in arriving at its opinion, Morgan Stanley used and relied upon management estimates provided by the management of Spirit on February 3, 2022 (the “Spirit Management Forecasted Financial Information”) and management estimates provided by the management of Frontier on January 20, 2022 (the “Frontier Management Forecasted Financial Information”), as more fully described in the section entitled “The Merger—Unaudited Prospective Financial Information”, each of which were approved by Spirit management for Morgan Stanley’s use in connection with its financial analyses.

Public Trading Benchmark Analysis

Morgan Stanley performed a public trading benchmark analysis, which is designed to provide an implied value of a company by comparing it to similar companies that are publicly traded. Morgan Stanley reviewed and compared certain financial estimates for each of Spirit and Frontier with comparable publicly available consensus equity analyst research estimates for selected companies that, in Morgan Stanley’s professional judgment, share certain similar business characteristics with and have certain comparable operating characteristics, including, among other things, product characteristics, similarly sized revenue and/or revenue growth rates, market capitalization, profitability, scale and/or other similar operating characteristics, to those of Spirit and Frontier, as applicable (which companies are referred to as the comparable companies) (the “Spirit Consensus Forecasted Financial Information of Spirit” and the “Spirit Consensus Forecasted Financial Information of Frontier”).

In the case of applying the analysis to Spirit, Frontier was included in the group of comparable companies. In the case of applying the analysis to Frontier, Spirit was included in the group of comparable companies. For purposes of this analysis, Morgan Stanley analyzed the ratio of adjusted enterprise value (“Adj. EV”), which Morgan Stanley defined as fully diluted market capitalization plus total debt, including capitalized operating lease liabilities, plus preferred stock, plus non-controlling interest, less cash and cash equivalents (including marketable securities and short term investments), to EBITDAR, which Morgan Stanley defined as operating income plus depreciation, amortization and rent expense plus addbacks for certain one-time costs, in each case estimated for the calendar year 2023, which ratio Morgan Stanley referred to as 2023E Adj. EV / EBITDAR. Morgan Stanley also analyzed the ratio of price per share as of February 4, 2022 to earnings per share estimated for the calendar year 2023, which ratio Morgan Stanley referred to as 2023E P / E.

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The below tables summarize the companies, the metrics and the multiples employed in this analysis:

Spirit Public Trading Benchmark Analysis

Based on its analysis and its professional judgment, Morgan Stanley selected a reference range of (i) 2023E Adj. EV / EBITDAR of 4.0x to 5.0x for Spirit and (ii) 2023E P / E of 8.0x to 10.0x for Spirit. Morgan Stanley applied the selected reference range to the corresponding financial estimates set forth in the Spirit Management Forecasted Financial Information and the Spirit Consensus Forecasted Financial Information of Spirit. Morgan Stanley’s analysis resulted in the following implied fully diluted share prices for Spirit common stock (rounded to the nearest $0.25):

Frontier Public Trading Benchmark Analysis

Based on its analysis and its professional judgment, Morgan Stanley selected a reference range of (i) 2023E Adj. EV / EBITDAR of 4.0x to 5.0x for Frontier and (ii) 2023E P / E of 8.0x to 10.0x for Frontier. Morgan Stanley applied the selected reference range to the corresponding financial estimates set forth in the Frontier Management Forecasted Financial Information and the Spirit Consensus Forecasted Financial Information of Frontier. Morgan Stanley’s analysis resulted in the following implied fully diluted share prices for Frontier common stock (rounded to the nearest $0.25):

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Exchange Ratio Implied by Public Trading Benchmark Analysis

Morgan Stanley then calculated the estimated implied cash adjusted exchange ratio range as set forth in the table below. Morgan Stanley calculated the low end of the exchange ratio range by dividing the lowest per share price for Spirit common stock resulting from the application of the relevant multiples described above, less the $2.13 cash consideration to be received in the merger, by the highest per share price for Frontier common stock resulting from the application of the relevant multiples described above. Morgan Stanley calculated the high end of the exchange ratio range by dividing the highest per share price for Spirit common stock resulting from the application of the relevant multiples described above, less the $2.13 cash consideration to be received in the merger, by the lowest per share price for Frontier common stock resulting from the application of the relevant multiples described above. The implied cash adjusted exchange ratio range (rounded to one decimal place) resulting from this analysis was as follows:

Morgan Stanley noted that the exchange ratio was 1.9126x.

No company utilized in the public trading benchmark analysis is identical to either Spirit or Frontier or directly comparable in business mix, size or other metrics. Accordingly, an analysis of the results of the foregoing analysis necessarily involves complex considerations and judgments concerning differences between Spirit and Frontier and the companies being compared and other factors that would affect the value of the companies to which Spirit and Frontier are being compared. In selecting comparable companies, Morgan Stanley made numerous judgments and assumptions with respect to size, business mix, industry performance, general business, regulatory, economic, market and financial conditions and other matters, many of which are beyond the control of Spirit or Frontier. These include, among other things, the impact of competition on Spirit’s or Frontier’s business and the industry generally, industry growth, and the absence of any adverse material change in the financial condition and prospects of Spirit or Frontier, the industry, or in the financial markets in general, which could affect the public trading value of Spirit and Frontier or the companies to which they are being compared.

Discounted Cash Flow Analysis

Morgan Stanley performed a discounted cash flow analysis on each of Spirit and Frontier, which is designed to provide an implied value of a company by calculating the present value of the estimated future cash flows and terminal value of such company. In connection with this analysis, Morgan Stanley calculated a range of per share equity values for each of Spirit and Frontier.

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Spirit Discounted Cash Flow Analysis

Morgan Stanley calculated the estimated present value of the stand-alone unlevered free cash flows that Spirit was forecasted to generate for the calendar years 2022 through 2026 on a standalone basis. Financial data used in this analysis were based on the Spirit Management Forecasted Financial Information.

Morgan Stanley performed this analysis on the estimated future cash flows contained in the Spirit Management Forecasted Financial Information as set forth in the section entitled “The Merger—Unaudited Prospective Financial Information”. For purposes of this analysis, unlevered free cash flows were calculated as Adjusted EBITDAR less rent expense, less unlevered cash tax expense (taking into account net operating losses and other differences between accounting tax expense and cash taxes paid), less change in net working capital, less change in deferred heavy maintenance, less capital expenditures (including pre-delivery deposits for flight equipment, net of refunds, and proceeds from sale of property and equipment), plus certain other non-cash expenses. These estimated unlevered free cash flows were reviewed and approved by Spirit management for Morgan Stanley’s use.

Morgan Stanley calculated terminal values for Spirit by applying a range of multiples of Adj. EV / EBITDAR of 5.5x to 7.0x, based on Morgan Stanley’s professional judgment, to the Adjusted EBITDAR of Spirit for the calendar year 2026. Morgan Stanley then adjusted the terminal value for the capitalized operating leases at December 31, 2026 (based on the Spirit Management Forecasted Financial Information) and discounted the unlevered free cash flows and terminal value to present value as of December 31, 2021 using mid-year convention (except for terminal value which was discounted using end-of-period methodology) and a range of discount rates from 9.8% to 11.4%, which were selected based on Morgan Stanley’s professional judgment to reflect an estimate of Spirit’s weighted average cost of capital (“WACC”). To calculate the implied per share equity value, Morgan Stanley then divided the implied equity value by the number of fully diluted shares of Spirit common stock outstanding as of February 4, 2022, as provided by Spirit management on February 4, 2022 using the treasury stock method.

Based on this analysis, Morgan Stanley derived the following ranges of implied equity value per share of Spirit common stock on a fully-diluted basis (rounded to the nearest $0.25):

Frontier Discounted Cash Flow Analysis

Morgan Stanley calculated the estimated present value of the stand-alone unlevered free cash flows that Frontier was forecasted to generate for the calendar years 2022 through 2026 on a standalone basis. Financial data used in this analysis were based on the Frontier Management Forecasted Financial Information.

Morgan Stanley performed this analysis on the estimated future cash flows contained in the Frontier Management Forecasted Financial Information as set forth in the section entitled “The Merger—Unaudited Prospective Financial Information”. For purposes of this analysis, unlevered free cash flows were calculated as Adjusted EBITDAR less rent expense, less unlevered cash tax expense (taking into account net operating losses and other differences between accounting tax expense and cash taxes paid), less change in net working capital, less change in deferred heavy maintenance, less capital expenditures (including pre-delivery deposits for flight equipment, net of refunds), less gains recognized on sale-leasebacks transactions, and plus proceeds from sale-leaseback transactions. These estimated unlevered free cash flows were reviewed and approved by Spirit management for Morgan Stanley’s use.

Morgan Stanley calculated terminal values for Frontier by applying a range of multiples of Adj. EV / EBITDAR of 5.5x to 7.0x, based on Morgan Stanley’s professional judgment, to the Adjusted EBITDAR of Frontier for the

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calendar year 2026. Morgan Stanley then adjusted the terminal value for the capitalized operating leases at December 31, 2026 (based on the Frontier Management Forecasted Financial Information) and discounted the unlevered free cash flows and terminal value to present value as of December 31, 2021 using mid-year convention (except for terminal value which was discounted using end-of-period methodology) and a range of discount rates from 9.5% to 11.2%, which were selected based on Morgan Stanley’s professional judgment to reflect an estimate of Frontier’s WACC. To calculate the implied per share equity value, Morgan Stanley then divided the implied equity value by the number of fully diluted shares of Frontier common stock outstanding as of February 4, 2022, as provided by Frontier management on February 4, 2022 using the treasury stock method.

Based on this analysis, Morgan Stanley derived the following ranges of implied equity value per share of Frontier common stock on a fully-diluted basis (rounded to the nearest $0.25):

Exchange Ratio Implied by Discounted Cash Flow Analysis

Morgan Stanley then calculated the estimated cash adjusted exchange ratio range implied by the discounted cash flow analysis as set forth in the table below. Morgan Stanley calculated the low end of the exchange ratio range by dividing the lowest implied share price for Spirit common stock, less the $2.13 cash consideration to be received in the merger, by the highest implied share price for Frontier common stock. Morgan Stanley calculated the high end of the exchange ratio range by dividing the highest implied share price for Spirit common stock, less the $2.13 cash consideration to be received in the merger, by the lowest implied share price for Frontier common stock. The implied cash adjusted exchange ratio range (rounded to one decimal place) resulting from this analysis was as follows:

Morgan Stanley noted that the exchange ratio was 1.9126x.

Discounted Equity Value Analysis

Morgan Stanley performed a discounted equity value analysis, which is designed to provide insight into the potential future equity value of a company as a function of the company’s estimated future earnings. The resulting equity value is subsequently discounted to arrive at an estimate of the implied present value for such company’s potential future equity value. In connection with this analysis, Morgan Stanley calculated a range of implied present equity values per share on a stand-alone basis for each of Spirit and Frontier.

Spirit Discounted Equity Value Analysis

To calculate the discounted equity value for Spirit, Morgan Stanley utilized estimated calendar year 2025 EBITDAR and estimated calendar year 2025 earnings per share based on the Spirit Management Forecasted Financial Information. Based upon the application of its professional judgment and experience after reviewing and comparing certain financial estimates for Spirit, Morgan Stanley applied a range of multiples of Adj. EV / EBITDAR for the 12-month period following January 1, 2025 of 5.0x to 6.5x, and a range of multiples of P / E

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for the 12-month period following January 1, 2025 of 9.0x to 11.0x, respectively, to these estimates, which ranges were selected based upon Morgan Stanley’s professional judgment and experience taking into account Spirit’s historical long-term trading multiples, and discounted the resulting values to December 31, 2021 at a discount rate of 12.0% based on Morgan Stanley’s estimate of Spirit’s then-current cost of equity.

Based on this analysis, Morgan Stanley derived the following ranges of implied equity value per share of Spirit common stock on a fully-diluted basis (rounded to the nearest $0.25):

Frontier Discounted Equity Value Analysis

To calculate the discounted equity value for Frontier, Morgan Stanley utilized estimated calendar year 2025 EBITDAR and estimated calendar year 2025 earnings per share based on the Frontier Management Forecasted Financial Information. Based upon the application of its professional judgment and experience after reviewing and comparing certain financial estimates for Frontier, Morgan Stanley applied a range of multiples of Adj. EV / EBITDAR for the 12-month period following January 1, 2025 of 5.0x to 6.5x, and a range of multiples of NTM P / E for the 12-month period following January 1, 2025 of 9.0x to 11.0x, respectively, to these estimates, which ranges were selected based upon Morgan Stanley’s professional judgment and experience taking into account Frontier’s historical long-term trading multiples, and discounted the resulting values to December 31, 2021 at a discount rate of 11.1% based on Morgan Stanley’s estimate of Frontier’s then-current cost of equity.

Based on this analysis, Morgan Stanley derived the following ranges of implied equity value per share of Frontier common stock on a fully-diluted basis (rounded to the nearest $0.25):

Exchange Ratio Implied by Discounted Equity Value Analysis