ULCC / Frontier Group Holdings, Inc. - Pengajuan SECLaporan Tahunan, Pernyataan Proksi

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): August 5, 2025 Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorporation) (Commi

Frontier Group Holdings, Inc. Condensed Consolidated Statements of Operations (unaudited, in millions, except share and per share data)

Frontier Airlines Reports Second Quarter 2025 Financial Results DENVER - August 5, 2025 - Frontier Group Holdings, Inc.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q (Mark One) ☑ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2025 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-40304 Frontier G

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): May 20, 2025 Frontier Group Holdi

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): May 20, 2025 Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorporation) (Commiss

Financial Statements and Exhibits, Submission of Matters to a Vote of Security Holders

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): May 15, 2025 Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorporation) (Commiss

Amended and Restated Certificate of Incorporation of Frontier Group Holdings, Inc.

Exhibit 3.1 AMENDED AND RESTATED CERTIFICATE OF INCORPORATION OF FRONTIER GROUP HOLDINGS, INC. Frontier Group Holdings, Inc. (the “Corporation”), a corporation organized and existing under the laws of the General Corporation Law of the State of Delaware (as the same exists or may hereafter be amended, the “DGCL”), does hereby certify as follows: 1. The name of the Corporation is Frontier Group Hol

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): May 12, 2025 Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorporation) (Commiss

Frontier Group Holdings, Inc. Condensed Consolidated Statements of Operations (unaudited, in millions, except share and per share data)

Frontier Airlines Reports First Quarter 2025 Financial Results DENVER - May 1, 2025 - Frontier Group Holdings, Inc.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q (Mark One) ☑ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2025 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-40304 Frontier

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): May 1, 2025 Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorporation) (Commissi

Form of Performance Stock Unit and Grant Agreement under the 2021 Equity Incentive Plan.

Exhibit 10.1 FRONTIER GROUP HOLDINGS, INC. 2021 INCENTIVE AWARD PLAN PERFORMANCE STOCK UNIT AWARD GRANT NOTICE Frontier Group Holdings, Inc., a Delaware corporation, (the “Company”), pursuant to its 2021 Incentive Award Plan, as amended from time to time (the “Plan”), hereby grants to the holder listed below (the “Participant”) an award of performance stock units (“Performance Stock Units” or “PSU

Regulation FD Disclosure, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): April 10, 2025 Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorporation) (Commi

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A INFORMATION Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.  )

TABLE OF CONTENTS UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A INFORMATION Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.  ) Filed by the Registrant ☒ Filed by a party other than the Registrant  ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permit

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A INFORMATION Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.  )

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A INFORMATION Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.  ) Filed by the Registrant ☒ Filed by a party other than the Registrant  ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A INFORMATION Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.  )

TABLE OF CONTENTS UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A INFORMATION Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.  ) Filed by the Registrant ☒ Filed by a party other than the Registrant  ☐ Check the appropriate box: ☒ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permit

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): March 7, 2025 Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorporation) (Commis

As filed with the Securities and Exchange Commission on February 18, 2025

As filed with the Securities and Exchange Commission on February 18, 2025 Registration No.

List of subsidiaries.

Exhibit 21.1 List of Subsidiaries of Frontier Group Holdings, Inc. Subsidiaries Jurisdiction of Incorporation or Organization Frontier Airlines Holdings, Inc. Delaware Frontier Airlines, Inc. Colorado

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K (Mark One) ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2024 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-40304 Frontier Group

Omnibus Amendment No. 1 to Revolving Loan and Guaranty Agreement, dated as of December 27, 2024, by and among Frontier Brand Intellectual Property, Ltd. and Frontier Loyalty Programs, Ltd., as borrowers, Frontier Airlines, Inc., Frontier Airlines Holdings, Inc., Frontier Group Holdings, Inc., Frontier Finance 1, Ltd., and Frontier Finance 2, Ltd., as guarantors, the lenders party thereto, and Citibank, N.A., as administrative and collateral agent, depository and securities intermediary.

Exhibit 10.24(b) Execution Version OMNIBUS AMENDMENT NO. 1 OMNIBUS AMENDMENT NO. 1 (this “Amendment No. 1”) dated as of December 27, 2024 (the “Original Closing Date”), among FRONTIER BRAND INTELLECTUAL PROPERTY, LTD., an exempted company with limited liability continued and existing under the laws of Bermuda (“Brand IP Borrower”), FRONTIER LOYALTY PROGRAMS, LTD., an exempted company with limited

Amendment No. Four to Codeshare Agreement, dated as of November 4, 2024, by and between Frontier Airlines, Inc. and Concesionaria Vuela Compania Aviacion S.A.P.I. de C.V.

Exhibit 10.27(e) AMENDMENT NO. FOUR TO CODESHARE AGREEMENT THIS AMENDMENT NUMBER FOUR TO THE CODESHARE AGREEMENT ( “Amendment Four”), dated as of the date of last signature below, is between Frontier Airlines, Inc. (“Frontier''), a corporation organized under the laws of Colorado, having its principal place of business at 4545 Airport Way, Denver, Colorado, 80239 United States of America, and Conc

Filing Fee Table

Exhibit 107.1 Calculation of Filing Fee Table Form S-8 (Form Type) Frontier Group Holdings, Inc. (Exact Name of Registrant as Specified in its Charter) Table 1: Newly Registered Securities Security Type Security Class Title Fee Calculation Rate Amount Registered(a) Proposed Maximum Offering Price Per Unit Maximum Aggregate Offering Price Fee Rate Amount of Registration Fee Equity Common Stock, $0.

Description of Securities Registered Pursuant to Section 12 of the Securities Exchange Act of 1934.

Exhibit 4.1 DESCRIPTION OF THE REGISTRANT’S SECURITIES REGISTERED PURSUANT TO SECTION 12 OF THE SECURITIES EXCHANGE ACT OF 1934 Frontier Group Holdings, Inc. (“we,” “our,” and “us”) has one class of securities registered under Section 12 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”): our voting common stock. The following description of our capital stock and provisions of

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Exhibit 99.3 From: Ted Christie <###> Sent: Friday, February 7, 2025 2:24 PM To: Bill Franke <###>; Andrew Broderick <###>; Brian Franke <###> Cc: Thomas Canfield <###> Subject: Counter Bill: Thank you again for your constructive proposal earlier this week. We very much appreciate the move, and have worked diligently to re-restrict our key stakeholders and coordinate with them on a counterproposal

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): February 11, 2025 Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorporation) (Co

Privileged and Confidential – Subject to NDA Prepared at the Direction of Counsel Subject to FRE 408 and State Equivalents Transaction Proposal Frontier (2/4) Spirit (2/7) ▪ Frontier and Spirit to combine as part of Spirit’s ongoing chapter ▪ Agreed

Exhibit 99.4 Pr Pri iv viil leg eged ed an and d Co Con nf fi ide dennti tia al l –– S Su ubj bjeec ct to t to ND NDA A Pr Prepar epareed d at at the D the Di ir reec cti tio on n of of Co Cou un ns sel el S Su ubj bjeec ct t to toR R FFE E 40 408 8 an and d S State tatequ q EEui iva vallen ents ts Project Galaxy Transaction Proposal February 7, 2025 1 Privileged and Confidential – Subject to NDA

Illustrative Capitalization Excluding $350mm Equity Rights Offering Sources & Uses Pro Forma Capitalization Falcon Saturn (-) Debt (+/-) Debt (-) Trxn (+/-) Total Pro Forma ($ in millions) $ Amount ($ in millions) 2/28/2025 2/28/2025 Paydown Restruct

Exhibit 99.2 Presentation to Spirit Alternative Proposal February 4, 2025 | Strictly private and confidential Illustrative Capitalization Excluding $350mm Equity Rights Offering Sources & Uses Pro Forma Capitalization Falcon Saturn (-) Debt (+/-) Debt (-) Trxn (+/-) Total Pro Forma ($ in millions) $ Amount ($ in millions) 2/28/2025 2/28/2025 Paydown Restructuring Fees Adjs. 2/28/2025 Cash and Shor

to determine valuation shares between the various of equity in the Spirit creditors and equity combined enterprise holders (e.g., VWAP) ERO Breakup • Required parties agree to • Required parties to • Required parties agree to Fee waive existing $35 m

Exhibit 99.6 Transaction Proposal Frontier (2/4) Spirit (2/7) Frontier (2/9) Structure • Frontier and Spirit to• Agreed• Agreed combine • Frontier to raise $800 million • Agreed• Agreed new money first lien debt • New $400 million revolver to • Agreed• Agreed be issued at close Debt • Spirit and its stakeholders to• Spirit and its• Spirit and its stakeholders to Consideration receive $400 million

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Exhibit 99.1 From: Link, Brian [BKG-IB] <###> Sent: Tuesday, February 4, 2025 20:42 To: Diego Simonian <###>; Bruce Mendelsohn <###> Cc: Grier, John F [BKG-IB] <###>; Patel, Sagar1 [BKG-IB] <###> Subject: Follow-up On behalf of Frontier Group Holdings, Inc. (“Frontier”), please find below key terms of Frontier’s revised proposal (“Revised Proposal”). Also attached is a summary capitalization sched

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Exhibit 99.5 From: Biffle, Barry <###> Sent: Monday, February 10, 2025 2:03 PM To: Ted Christie Subject: Update Attachments: Transaction Proposal (Falcon Response 292025).pdf Dear Ted, Attached is in response to your email dated 2/07/2025. As we advised you when we sent our last proposal, eliminating the $350 million equity rights offering was a significant concession and we would not agree to mat

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K/A (Amendment No. 1) CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): June 20, 2024 Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of in

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): February 6, 2025 Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorporation) (Com

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): February 7, 2025 Frontier Group H

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): February 7, 2025 Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorporation) (Com

Frontier Group Holdings, Inc. Consolidated Statements of Operations (unaudited, in millions, except percentages and share and per share amounts)

Frontier Airlines Reports Solid Fourth Quarter 2024 Financial Results on Record Revenue DENVER - February 7, 2025 - Frontier Group Holdings, Inc.

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Exhibit 99.3 Frontier Airlines, Inc. 4545 Airport Way Denver, Colorado 80239 Confidential Mr. H. McIntyre Gardner Chairman of the Board Mr. Edward M. Christie III President and Chief Executive Officer Spirit Airlines, Inc. 1731 Radiant Drive Dania Beach. FL 33004 January 16, 2025 Dear Mr. Gardner and Mr. Christie: In response to your letter dated January 11, 2025, it appears the parties continue t

Frontier Group Holdings, Inc.

Exhibit 99.2 CONFIDENTIAL Frontier Group Holdings, Inc. 4545 Airport Way Denver, Colorado 80239 Attn: Mr. W. Franke, Mr. B. Biffle January 11, 2025 Gentlemen: Thank you for your letter dated January 7, 2025. We are of course always exploring and open to ideas and proposals that maximize value for our Company and its stakeholders, and we share your view that a combination of our two companies has l

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Exhibit 99.6 From: Bill Franke Sent: Tuesday, January 28, 2025 4:39 PM To: Mac Gardner - Spirit Airlines (###) <###>; ### Subject: Confidential Dear Mr. Gardner and Mr. Christie: As has been confirmed in our discussions with you and your advisors, both parties agree there is compelling industrial logic to the combination of our two companies. To that end, we have proposed to you a transaction, as

Presentation to Spirit January 2025

Exhibit 99.7 Presentation to Spirit January 2025 Frontier’s proposal ensures superior economics, certainty, and speed for Spirit’s stakeholders relative to the Spirit standalone plan Stronger, More Competitive Airline ïƒ~ Transaction with Frontier creates America’s first low-cost carrier with sufficient scale to compete with the Big Fourïƒ~ Complementary networks bring more low fares to more marke

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Exhibit 99.5 From: Grier, John F [BKG-IB] <###> Sent: Friday, January 24, 2025 3:34 PM To: ### Cc: Adavikolanu, Rohith [BKG-IB] Subject: FW: Top Gun response to Whatley Mark, I asked Barry and Bill to address some of the questions you asked yesterday. Their response is below. Roh and I are happy to follow up at your convenience. Best, John Sent with BlackBerry Work (www.blackberry.com) From: [flyf

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Exhibit 99.8 CONFIDENTIAL Frontier Group Holdings, Inc. 4545 Airport Way Denver, Colorado 80239 Attn: Mr. W. Franke, Mr. B. Biffle January 28, 2025 Gentlemen: Thank you again for your proposal letter dated January 7, 2025 (the “Proposal”), and for engaging with us and with our stakeholders. As we have previously told you, we are always, and remain, open to executable ideas and proposals that maxim

Frontier’s proposal ensures superior economics, certainty, and speed for Spirit’s stakeholders relative to the Spirit standalone plan Stronger, More Competitive Airline ïƒ~ Transaction with Frontier creates America’s first

Exhibit 99.4 Exhibit 99.4 Presentation to Spirit January 2025 Frontier’s proposal ensures superior economics, certainty, and speed for Spirit’s stakeholders relative to the Spirit standalone plan Stronger, More Competitive Airline ïƒ~ Transaction with Frontier creates America’s first low-cost carrier with sufficient scale to compete with the Big Fourïƒ~ Complementary networks bring more low fares

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): January 29, 2025 Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorporation) (Com

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Exhibit 99.1 Frontier Airlines, Inc. 4545 Airport Way Denver, Colorado 80239 Confidential Mr. H. McIntyre Gardner Chairman of the Board Mr. Edward M. Christie III President and Chief Executive Officer Spirit Airlines, Inc. 1731 Radiant Drive Dania Beach, FL 33004 January 7, 2025 Dear Mr. Gardner and Mr. Christie: On behalf of Frontier Group Holdings, Inc. (“Frontier”), we are pleased to submit our

Regulation FD Disclosure

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): January 6, 2025 Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorporation) (Comm

Regulation FD Disclosure

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): December 3, 2024 Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorporation) (Com

ULCC / Frontier Group Holdings, Inc. / Indigo Frontier Holdings Company, LLC - SC 13G/A Passive Investment

SC 13G/A 1 d812074dsc13ga.htm SC 13G/A Securities and Exchange Commission Washington, D.C. 20549 Schedule 13G (Rule 13d-102) Information to be Included in Statements Filed Pursuant to § 240.13d-1(b), (c) and (d) and Amendments Thereto Filed Pursuant to § 240.13d-2 UNDER THE SECURITIES EXCHANGE ACT OF 1934 (Amendment No. 2)* Frontier Group Holdings, Inc. (Name of Issuer) Common Stock (Title of Clas

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): October 28, 2024 Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorporation) (Com

Amendment No. 18 to Airbus A320 Family Aircraft Purchase Agreement, dated as of July 31, 2024, by and between Airbus S.A.S. and Frontier Airlines, Inc.

[***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10).

Third Amendment to the Amended and Restated Frontier Airlines, Inc. Credit Card Affinity Agreement, dated as of September 6, 2024, by and between Barclays Bank Delaware and Frontier Airlines, Inc.

[***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10).

Fourth Quarter

Frontier Airlines Reports Third Quarter 2024 Financial Results DENVER - October 29, 2024 - Frontier Group Holdings, Inc.

Revolving Loan and Guaranty Agreement, dated as of September 26, 2024, by and among Frontier Brand Intellectual Property, Ltd. and Frontier Loyalty Programs, Ltd., as borrowers, Frontier Airlines, Inc., Frontier Group Holdings, Inc., Frontier Airlines Holdings, Inc., Frontier Finance 1, Ltd., Frontier Finance 2, Ltd. and the other guarantors from time to time party thereto, as guarantors, Citibank N.A., as administrative agent and collateral agent, and the lenders party thereto.

[***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q (Mark One) ☑ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2024 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-40304 Front

Step-In Agreement, dated as of September 26, 2024, by and between Frontier Group Holdings, Inc., as guarantor, Frontier Airlines, Inc., as original buyer, Vertical Horizons JSA Limited, as buyer, JSA International U.S. Holdings, LLC, as financier, and Airbus S.A.S.

[***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10).

Tenth Amended and Restated Credit Agreement, dated as of September 26, 2024, by and among Vertical Horizons, Ltd., as borrower, each lender identified on Schedule I thereto, and Bank of Utah, not in its individual capacity but solely as security trustee.

[***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10).

Amended and Restated Step-In Agreement, dated as of September 26, 2024, by and among Vertical Horizons, Ltd., as buyer, Bank of Utah, not in its individual capacity but solely as security trustee, and Airbus S.A.S.

[***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10).

Amendment No. 19 to Airbus A320 Family Aircraft Purchase Agreement, dated as of September 25, 2024, by and between Airbus S.A.S. and Frontier Airlines, Inc.

[***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10).

Credit Agreement, dated as of September 26, 2024, by and among Vertical Horizons JSA Limited, as borrower, JSA International U.S. Holdings, LLC, as lender and administrative agent, and Bank of Utah, not in its individual capacity but solely as security trustee.

[***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10).

Fourth Amendment to the Amended and Restated Frontier Airlines, Inc. Credit Card Affinity Agreement, dated as of September 26, 2024, by and between Barclays Bank Delaware and Frontier Airlines, Inc.

[***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10).

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): October 29, 2024 Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorporation) (Com

Entry into a Material Definitive Agreement, Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): September 26, 2024 Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorporation) (C

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): September 11, 2024 Frontier Group

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): September 11, 2024 Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorporation) (C

Form of Common Stock Warrant

Exhibit 4.2 Warrant No. CS-[] FORM OF WARRANT TO PURCHASE COMMON STOCK WARRANT to purchase Shares of Common Stock of Frontier Group Holdings, Inc. Issue Date: [] 1. Definitions. Unless the context otherwise requires, when used herein the following terms shall have the meanings indicated. “Affiliate” means, with respect to any person, any person directly or indirectly controlling, controlled by or

Amendment No. One to Codeshare Agreement, dated as of May 22, 2018, by and between Frontier Airlines, Inc. and Concesionaria Vuela Compania Aviacion S.A.P.I. de C.V.

[***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10).

Amendment No. Three to Codeshare Agreement, dated as of April 12, 2024, by and between Frontier Airlines, Inc. and Concesionaria Vuela Compania Aviacion S.A.P.I. de C.V.

Exhibit 10.3 AMENDMENT NO. THREE TO CODESHARE AGREEMENT THIS AMENDMENT NUMBER THREE TO THE CODESHARE AGREEMENT ( “Amendment Three”), dated as of the date of last signature below, is between Frontier Airlines, Inc. (“Frontier”), a corporation organized under the laws of Colorado, having its principal place of business at 4545 Airport Way, Denver, Colorado, 80239 United States of America, and Conces

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q (Mark One) ☑ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2024 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-40304 Frontier G

Amendment No. Two to Codeshare Agreement, dated as of February 14, 2019, by and between Frontier Airlines, Inc. and Concesionaria Vuela Compania Aviacion S.A.P.I. de C.V.

Exhibit 10.2 AMENDMENT NO. TWO TO CODESHARE AGREEMENT THIS AMENDMENT NUMBER TWO TO THE CODESHARE AGREEMENT ( "Amendment Two"), dated as of the date of last signature below, is between Frontier Airlines, Inc. ("Frontier"), a corporation organized under the laws of Colorado, having its principal place of business at 4545 Airport Way, Denver, Colorado, 80239 United States of America, and Concesionari

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): August 8, 2024 Frontier Group Hol

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): August 8, 2024 Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorporation) (Commi

Third Quarter

Frontier Airlines Reports Second Quarter 2024 Financial Results DENVER - August 8, 2024 - Frontier Group Holdings, Inc.

Amendments to Articles of Incorporation or Bylaws; Change in Fiscal Year, Financial Statements and Exhibits

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): July 24, 2024 Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorporation) (Commis

Amended and Restated Bylaws of Frontier Group Holdings, Inc.

Exhibit 3.1 AMENDED AND RESTATED BYLAWS OF FRONTIER GROUP HOLDINGS, INC. (a Delaware corporation) as of July 24, 2024 TABLE OF CONTENTS Page ARTICLE I - CORPORATE OFFICES 1 1.1 REGISTERED OFFICE 1 1.2 OTHER OFFICES 1 ARTICLE II - MEETINGS OF STOCKHOLDERS 1 2.1 PLACE OF MEETINGS 1 2.2 ANNUAL MEETING 1 2.3 SPECIAL MEETING 1 2.4 ADVANCE NOTICE PROCEDURES FOR BUSINESS BROUGHT BEFORE A MEETING 2 2.5 AD

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): June 20, 2024 Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorporation) (Commis

Frontier Group Holdings, Inc. Announces New Board Member

Frontier Group Holdings, Inc. Announces New Board Member DENVER – June 25, 2024 - Frontier Group Holdings, Inc. (NASDAQ: ULCC), parent company of Frontier Airlines, Inc., today announced the appointment of Nancy L. Lipson to the company’s Board of Directors. “We are very pleased to have Ms. Lipson join the Frontier Board of Directors,” said William A. Franke, chairman of Frontier Group Holdings, I

Submission of Matters to a Vote of Security Holders

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): May 23, 2024 Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorporation) (Commiss

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): May 10, 2024 Frontier Group Holdi

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): May 10, 2024 Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorporation) (Commiss

Second Quarter

Frontier Airlines Reports First Quarter 2024 Financial Results DENVER - May 2, 2024 - Frontier Group Holdings, Inc.

Employment Letter, dated as of November 30, 2023, by and between Frontier Airlines, Inc. and Alex Clerc

1 November 30, 2023 Alex Clerc Dallas, TX Re: Offer Letter – SVP, Customers Dear Alex: Frontier Airlines, Inc.

, 2024, by and between Frontier Airlines, Inc. and Howard M. Diamond

US-DOCS\147905540.1 February 6, 2024 VIA E-MAIL [###] Mr. Howard M. Diamond Re: Employment Terms Dear Howard: Frontier Airlines, Inc. (“Frontier”) is pleased to promote you to the position of Executive Vice President, Legal and Corporate Affairs effective as of February 1, 2024 (the “Effective Date”). You will have such duties as are normally associated with this position and such duties as may be

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): May 2, 2024 Frontier Group Holdin

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): May 2, 2024 Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorporation) (Commissi

, dated as of February 6, 2024, by and between Frontier Airlines, Inc. and Steven

US-DOCS\147905540.1 February 6, 2024 VIA E-MAIL [###] Mr. Steven C. Schuller Re: Employment Terms Dear Steve: Frontier Airlines, Inc. (“Frontier”) is pleased to promote you to the position of Senior Vice President, Human Resources effective as of February 1, 2024 (the “Effective Date”). You will have such duties as are normally associated with this position and such duties as may be modified or su

Employment Letter, dated as of February 29, 2024, by and between Frontier Airlines, Inc. and Robert Schroeter

US-DOCS\144862550.6 February 29, 2024 Robert Schroeter 1504 NE 4th Place Fort Lauderdale, FL 33301 Re: Offer Letter – SVP, Chief Commercial Officer Dear Bobby: Frontier Airlines, Inc. (“Frontier”) is pleased to offer you the position of SVP, Chief Commercial Officer. You will have such duties as are normally associated with this position as such duties may be modified or supplemented by James Demp

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q (Mark One) ☑ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2024 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-40304 Frontier

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A INFORMATION Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.  ) Filed by the Registrant ☒ Filed by a party other than

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A INFORMATION Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.  ) Filed by the Registrant ☒ Filed by a party other than the Registrant  ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A INFORMATION Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.  )

TABLE OF CONTENTS UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A INFORMATION Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.  ) Filed by the Registrant ☒ Filed by a party other than the Registrant  ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permit

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A INFORMATION Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.  ) Filed by the Registrant ☒ Filed by a party other than

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A INFORMATION Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.  ) Filed by the Registrant ☒ Filed by a party other than the Registrant  ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(

ULCC / Frontier Group Holdings, Inc. / Group Holdings - Frontier LLC - SC 13G Passive Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. )* Frontier Group Holdings, Inc. (Name of Issuer) Common Stock, $0.001 par value (Title of Class of Securities) 35909R108 (CUSIP Number) April 5, 2024 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pur

ULCC / Frontier Group Holdings, Inc. / Wildcat Capital Management, LLC Passive Investment

United States Securities and Exchange Commission Washington, D.C. 20549 Schedule 13G (Rule 13d-102) Under the Securities Exchange Act of 1934 Information to Be Included in Statements Filed Pursuant to § 240.13d-1(b), (c) and (d) and Amendments Thereto Filed Pursuant to § 240.13d-2 (Amendment No. )* Frontier Group Holdings, Inc. (Name of Issuer) Common Stock, $0.001 par value per share (Title of Cl

Regulation FD Disclosure

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): March 29, 2024 Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorporation) (Commi

List of subsidiaries.

Exhibit 21.1 List of Subsidiaries of Frontier Group Holdings, Inc. Subsidiaries Jurisdiction of Incorporation or Organization Frontier Airlines Holdings, Inc. Delaware Frontier Airlines, Inc. Colorado

Policy for Recovery of Erroneously Awarded Compensation of Frontier Group Holdings, Inc., dated as of October 2, 2023.

US-DOCS\144335379.2 FRONTIER GROUP HOLDINGS, INC. POLICY FOR RECOVERY OF ERRONEOUSLY AWARDED COMPENSATION Frontier Group Holdings, Inc. (the “Company”) has adopted this Policy for Recovery of Erroneously Awarded Compensation (the “Policy”), effective as of October 2, 2023 (the “Effective Date”). Capitalized terms used in this Policy but not otherwise defined herein are defined in Section 11. 1. Pe

As filed with the Securities and Exchange Commission on February 20, 2024

As filed with the Securities and Exchange Commission on February 20, 2024 Registration No.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K (Mark One) ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2023 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-40304 Frontier Group

Employment Letter, dated as of October 16, 2023, by and between Frontier Airlines, Inc. and Mark

US-DOCS\145069770.4 October 16, 2023 VIA E-MAIL ([email protected]) Mr. Mark Mitchell Re: Employment Terms Dear Mark: Frontier Airlines, Inc. (“Frontier”) is pleased to promote you to the position of Senior Vice President, Chief Financial Officer effective as of October 16, 2023 (the “Effective Date”). You will have such duties as are normally associated with this position and such dut

Insider Trading Compliance Policy and Procedures

1 Frontier Group Holdings, Inc. Insider Trading Compliance Policy and Procedures February 27, 2023 Federal and state laws prohibit trading in the securities of a company while in possession of material nonpublic information and in breach of a duty of trust or confidence. These laws also prohibit anyone who is aware of material nonpublic information from providing this information to others who may

Filing Fee Table

Exhibit 107.1 Calculation of Filing Fee Table Form S-8 (Form Type) Frontier Group Holdings, Inc. (Exact Name of Registrant as Specified in its Charter) Table 1: Newly Registered Securities Security Type Security Class Title Fee Calculation Rate Amount Registered(a) Proposed Maximum Offering Price Per Unit Maximum Aggregate Offering Price Fee Rate Amount of Registration Fee Equity Common Stock, $0.

Form of Restricted Stock Unit Award Grant Notice and Restricted Stock Unit Award Agreement under the 2021 Incentive Award Plan, effective for grants after October 25, 2023.

US-DOCS\145660174.2 FRONTIER GROUP HOLDINGS, INC. 2021 INCENTIVE AWARD PLAN RESTRICTED STOCK UNIT AWARD GRANT NOTICE Frontier Group Holdings, Inc., a Delaware corporation, (the “Company”), pursuant to its 2021 Incentive Award Plan, as amended from time to time (the “Plan”), hereby grants to the holder listed below (the “Participant”), an award of restricted stock units (“Restricted Stock Units” or

mended and Restated Employment Agreement, dated as of October 16, 2023, by and between Frontier Airlines, Inc. and James G. Dempsey.

1 AMENDMENT TO AMENDED AND RESTATED EMPLOYMENT AGREEMENT THIS AMENDMENT TO THE AMENDED AND RESTATED EMPLOYMENT AGREEMENT (this “Amendment”), is made as of October 16, 2023 (the “Amendment Effective Date”), by and between Frontier Airlines, Inc.

Employment Letter, dated as of August 25, 2023, by and between Frontier Airlines, Inc. and Rajat Khanna.

Exhibit 10.10

Fifth Amended and Restated IAE Engine Benefits Agreement A320neo and A321neo Aircraft (2022, 2023, 2024 and 2025 Deliveries), dated as of December 19, 2023, among Vertical Horizons, Ltd., International Aero Engines, LLC, Bank of Utah, not in its individual capacity but solely as security trustee, and Frontier Airlines, Inc.

[***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10).

ULCC / Frontier Group Holdings, Inc. / Indigo Frontier Holdings Company, LLC - SC 13G/A Passive Investment

SC 13G/A 1 d28456dsc13ga.htm SC 13G/A Securities and Exchange Commission Washington, D.C. 20549 Schedule 13G (Rule 13d-102) Information to be Included in Statements Filed Pursuant to § 240.13d-1(b), (c) and (d) and Amendments Thereto Filed Pursuant to § 240.13d-2 UNDER THE SECURITIES EXCHANGE ACT OF 1934 (Amendment No. 1)* Frontier Group Holdings, Inc. (Name of Issuer) Common Stock (Title of Class

Regulation FD Disclosure, Financial Statements and Exhibits

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): February 6, 2024 Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorporation) (Com

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): February 6, 2024 Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorporation) (Com

5 to 7%

Frontier Airlines Reports Fourth Quarter 2023 Financial Results DENVER - February 6, 2024 - Frontier Group Holdings, Inc.

Fourth quarter & FY2023 Financial Update February 6, 2024 2 Disclaimer This presentation (including the accompanying oral presentation) is being delivered on behalf of Frontier Group Holdings, Inc. ("Frontier") ("we", "our", "us", or the "Company").

Fourth quarter & FY2023 Financial Update February 6, 2024 2 Disclaimer This presentation (including the accompanying oral presentation) is being delivered on behalf of Frontier Group Holdings, Inc.

Ninth Amended and Restated Guarantee, dated as of August 11, 2023, by Frontier Airlines Holdings, Inc., as guarantor, in favor of Bank of Utah, not in its individual capacity but solely as security trustee.

Exhibit 10.6 CLIFFORD CHANCE US LLP 24006704141-v2 80-40605773 Execution Version DATED AS OF AUGUST 11, 2023 FRONTIER AIRLINES HOLDINGS, INC. AS GUARANTOR AND BANK OF UTAH NOT IN ITS INDIVIDUAL CAPACITY BUT SOLELY AS SECURITY TRUSTEE NINTH AMENDED AND RESTATED GUARANTEE IN RESPECT OF THE PDP FINANCING OF THIRTY- THREE (33) AIRBUS A320NEO AIRCRAFT AND SEVENTY-SIX (76) AIRBUS A321NEO AIRCRAFT 240067

Ninth Amended and Restated Credit Agreement, dated as of August11, 2023, by and among Vertical Horizons, Ltd., as borrower, Citibank, N.A., as facility agent and arranger, Bank of Utah, not in its individual capacity but solely as security trustee, and each lender identified on Schedule I thereto.

[***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10).

Second Amended and Restated Guarantee, dated as August 11, 2023, by Frontier Group Holdings, Inc., as guarantor, in favor of Bank of Utah, not in its individual capacity but solely as security trustee.

[***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10).

Amendment No. 17 to Airbus A320 Family Purchase Agreement, dated as of September 28, 2023, by and between Airbus S.A.S. and Frontier Airlines, Inc.

[***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10).

Amendment to Amended and Restated Step-In Agreement, dated as of October 13, 2023, by and among Vertical Horizons, Ltd., Bank of Utah, not in its individual capacity but solely as security trustee, and Airbus S.A.S.

[***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10).

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): October 26, 2023 Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorporation) (Com

Ninth Amended and Restated Guarantee, dated as of August 11, 2023, by Frontier Airlines, Inc., as guarantor, in favor of Bank of Utah, not in its individual capacity but solely as security trustee.

Exhibit 10.5 24006704137-v2 80-40605773 DATED AS OF AUGUST 11, 2023 FRONTIER AIRLINES INC. AS GUARANTOR AND BANK OF UTAH NOT IN ITS INDIVIDUAL CAPACITY BUT SOLELY AS SECURITY TRUSTEE NINTH AMENDED AND RESTATED GUARANTEE IN RESPECT OF THE PDP FINANCING OF THIRTY- THREE (33) AIRBUS A320NEO AIRCRAFT AND SEVENTY-SIX (76) AIRBUS A321NEO AIRCRAFT 24006704137-v2 80-40605773 CONTENTS Clause Page 1. Defini

Amended and Restated Step-In Agreement, dated as of August 11, 2023, by and among Vertical Horizons, Ltd., Bank of Utah, not in its individual capacity but solely as security trustee, and Airbus S.A.S.

[***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q (Mark One) ☑ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2023 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-40304 Front

Fourth Amended and Restated IAE Engine Benefits Agreement A320neo and A321neo Aircraft (2023, 2024, 2025 and 2026 Deliveries), dated as of August 11, 2023, among Vertical Horizons, Ltd., International Aero Engines, LLC, Bank of Utah, not in its individual capacity but solely as security trustee, and Frontier Airlines, Inc.

[***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10).

Amendment No. 16 to Airbus A320 Family Purchase Agreement, dated as of August 9, 2023, by and between Airbus S.A.S. and Frontier Airlines, Inc.

[***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10).

Amendment No. 1 to Ninth Amended and Restated Credit Agreement, dated as of October 13, 2023, by and among Vertical Horizons, Ltd., as borrower, Citibank N.A., as facility agent and arranger, Bank of Utah, not in its individual capacity but solely as security trustee, and each lender identified on the signature pages thereto.

[***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10).

Fourth Quarter

Frontier Airlines Reports Third Quarter 2023 Financial Results DENVER - October 26, 2023 - Frontier Group Holdings, Inc.

Frontier Airlines Names James G. Dempsey President and Mark C. Mitchell as CFO Also Announces New Leadership Appointments at CIO and Treasurer Positions

Exhibit 99.1 Frontier Airlines Names James G. Dempsey President and Mark C. Mitchell as CFO Also Announces New Leadership Appointments at CIO and Treasurer Positions DENVER – October 19, 2023 – Frontier Airlines, Inc., a subsidiary of Frontier Group Holdings, Inc. (NASDAQ: ULCC), today announced the promotion of James G. Dempsey to President, and Mark C. Mitchell to Senior Vice President and Chief

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): October 16, 2023 Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorporation) (Com

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): September 13, 2023 Frontier Group

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): September 13, 2023 Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorporation) (C

Entry into a Material Definitive Agreement, Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): August 11, 2023 Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorporation) (Comm

Agreement, dated April 26, 2023, by and among Frontier Airlines Holdings, Inc., on behalf of itself and Frontier Airlines, Inc., U.S. Bank National Association, acting through its Canadian branch, Elavon Company Canada, and Elavon Inc.

[***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10).

Second Amendment to the Amended and Restated Frontier Airlines, Inc. Credit Card Affinity Agreement, dated as of May 23, 2023, by and between Barclays Bank Delaware and Frontier Airlines, Inc.

[***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10).

Amendment No. 4 to Eighth Amended and Restated Credit Agreement, dated as of May 26, 2023, by and among Vertical Horizons, Ltd., as borrower, Citibank, N.A., as facility agent and arranger, Bank of Utah, not in its individual capacity but solely as security trustee, and each lender identified on the signature pages thereto.

Exhibit 10.2 CLIFFORD CHANCE US LLP EXECUTION VERSION DATED AS OF MAY 26, 2023 VERTICAL HORIZONS, LTD., AS BORROWER EACH LENDER IDENTIFIED ON THE SIGNATURE PAGE HERETO AS LENDERS CITIBANK, N.A., AS FACILITY AGENT CITIBANK, N.A., AS ARRANGER BANK OF UTAH, NOT IN ITS INDIVIDUAL CAPACITY BUT SOLELY AS SECURITY TRUSTEE AMENDMENT NO. 4 TO EIGHTH AMENDED AND RESTATED CREDIT AGREEMENT DATED AS OF JUNE 30

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q (Mark One) ☑ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2023 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-40304 Frontier G

dated as of June 28, 2023, by and among Vertical Horizons, Ltd., Bank of Utah, not in its individual capacity but solely as security trustee, and Airbus S.A.S.

[***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10).

Amendment No. 15 to Airbus A320 Family Purchase Agreement, dated as of June 28, 2023, by and between Airbus S.A.S. and Frontier Airlines, Inc.

[***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10).

First Amendment to the Amended and Restated Frontier Airlines, Inc. Credit Card Affinity Agreement, dated as of June 29, 2021, by and between Barclays Bank Delaware and Frontier Airlines, Inc.

[***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10).

Third Quarter

Frontier Airlines Reports Second Quarter 2023 Financial Results DENVER - August 1, 2023 - Frontier Group Holdings, Inc.

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): August 1, 2023 Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorporation) (Commi

Fourth Amendment to Amended and Restated Step-In Agreement, dated as of May 26, 2023, by and among Vertical Horizons, Ltd., Bank of Utah, not in its individual capacity but solely as security trustee, and Airbus S.A.S.

[***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): May 25, 2023 Frontier Group Holdi

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): May 25, 2023 Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorporation) (Commiss

Frontier Group Holdings, Inc. Condensed Consolidated Statements of Operations (unaudited, in millions, except for per share amounts)

Frontier Airlines Reports First Quarter 2023 Financial Results with Spring Break Outperforming Expectations DENVER - May 3, 2023 - Frontier Group Holdings, Inc.

Third Amendment Agreement, dated as of March 31, 2023, by and among Vertical Horizons, Ltd., Bank of Utah, not in its individual capacity but solely as security trustee, and Airbus S.A.S.

[***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q (Mark One) ☑ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2023 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-40304 Frontier

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): May 3, 2023 Frontier Group Holdin

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): May 3, 2023 Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of organization) (Commissio

Non-Employee Director Compensation Program, as amended on February 8, 2023.

Exhibit 10.1 FRONTIER GROUP HOLDINGS, INC. NON-EMPLOYEE DIRECTOR COMPENSATION PROGRAM Non-employee members of the board of directors (the “Board”) of Frontier Group Holdings, Inc. (the “Company”) shall be eligible to receive cash and equity compensation as set forth in this Non-Employee Director Compensation Program (this “Program”). The cash and equity compensation described in this Program shall

Amendment No. 2 to Eighth Amended and Restated Credit Agreement, dated as of March 1, 2023, by and among Vertical Horizons, Ltd., as borrower, Citibank, N.A., as facility agent and arranger, Bank of Utah, not in its individual capacity but solely as security trustee, and each lender identified on the signature pages thereto.

[***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10).

Amendment No. 3 to Eighth Amended and Restated Credit Agreement, dated as of March 31, 2023, by and among Vertical Horizons, Ltd., as borrower, Citibank, N.A., as facility agent and arranger, Bank of Utah, not in its individual capacity but solely as security trustee, and each lender identified on the signature pages thereto.

Exhibit 10.4 CLIFFORD CHANCE US LLP EXECUTION VERSION DATED AS OF MARCH 31, 2023 VERTICAL HORIZONS, LTD., AS BORROWER EACH LENDER IDENTIFIED ON THE SIGNATURE PAGE HERETO AS LENDERS CITIBANK, N.A., AS FACILITY AGENT CITIBANK, N.A., AS ARRANGER BANK OF UTAH, NOT IN ITS INDIVIDUAL CAPACITY BUT SOLELY AS SECURITY TRUSTEE AMENDMENT NO. 3 TO EIGHTH AMENDED AND RESTATED CREDIT AGREEMENT DATED AS OF JUNE

Amendment No. 14 to Airbus A320 Family Purchase Agreement, dated as of March 31, 2023, by and between Airbus S.A.S. and Frontier Airlines, Inc.

[***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A INFORMATION Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.  )

TABLE OF CONTENTS UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A INFORMATION Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.  ) Filed by the Registrant ☒ Filed by a party other than the Registrant  ☐ Check the appropriate box:  ☐ Preliminary Proxy Statement  ☐ Confidential, for Use of the Commission Only (as perm

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A INFORMATION Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.  ) Filed by the Registrant ☒ Filed by a party other than

proxynoticefinalforworki UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.

Filing Fee Table.

EX-FILING FEES Exhibit 107.1 Calculation of Filing Fee Table Form S-8 (Form Type) Frontier Group Holdings, Inc. (Exact Name of Registrant as Specified in its Charter) Table 1: Newly Registered Securities Security Type Security Class Title Fee Calculation Rule Amount Registered(1) Proposed Maximum Offering Price Per Unit Maximum Aggregate Offering Price Fee Rate Amount of Registration Fee Equity Co

Power of Attorney (included in the signature pages to the Registration Statement).

S-8 1 d424827ds8.htm FORM S-8 As filed with the Securities and Exchange Commission on February 22, 2023 Registration No. 333- UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM S-8 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 46-3681866 (State or other jurisdiction of

Amendment No. 12 to Airbus A320 Family Aircraft Purchase Agreement, dated as of March 31, 2022, by and between Airbus S.A.S. and Frontier Airlines, Inc.

EX-10.17CC 3 frontier-ex1017ccxairbusam.htm EX-10.17CC [***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10). Such excluded information is not material and would likely cause competitive harm to the registrant if publicly disclosed. Exhibit 10.17(cc) Amendment No. 12 This Amendment No. 12 (this “Amendment”) is entered into as of March 31, 2022, be

Amended and Restated Bylaws of Frontier Group Holdings, Inc.

EX-3.2 2 frontier-ex32xarbylawsxq422.htm EX-3.2 Exhibit 3.2 AMENDED AND RESTATED BYLAWS OF FRONTIER GROUP HOLDINGS, INC. (a Delaware corporation) TABLE OF CONTENTS Page ARTICLE I - CORPORATE OFFICES 1 1.1 REGISTERED OFFICE 1 1.2 OTHER OFFICES 1 ARTICLE II - MEETINGS OF STOCKHOLDERS 1 2.1 PLACE OF MEETINGS 1 2.2 ANNUAL MEETING 1 2.3 SPECIAL MEETING 1 2.4 ADVANCE NOTICE PROCEDURES FOR BUSINESS BROUG

Amendment No. 13 to Airbus A320 Family Aircraft Purchase Agreement, dated as of December 16, 2022, by and between Airbus S.A.S. and Frontier Airlines, Inc.

[***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10).

List of subsidiaries.

Exhibit 21.1 List of Subsidiaries of Frontier Group Holdings, Inc. Subsidiaries Jurisdiction of Incorporation or Organization Frontier Airlines Holdings, Inc. Delaware Frontier Airlines, Inc. Colorado

Amendment No. 1 to Eighth Amended and Restated Credit Agreement, dated as of December 29, 2022, by and among, Vertical Horizons, Ltd., as borrower, Citibank, N.A., as facility agent and arranger, Bank of Utah, not in its individual capacity but solely as security trustee, and each lender identified on the signature pages thereto.

[***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K (Mark One) ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2022 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-40304 Frontier Group

As filed with the Securities and Exchange Commission on February 15, 2023

As filed with the Securities and Exchange Commission on February 15, 2023 Registration No.

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): February 8, 2023 Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorporation) (Com

17% to 19%

Frontier Airlines Reports Fourth Quarter Profit on Strong Revenue and Cost Performance DENVER - February 8, 2023 - Frontier Group Holdings, Inc.

Investor Day NOVEMBER 15, 2022

Exhibit 99.1 Investor Day NOVEMBER 15, 2022 Welcome and Safe Harbor DAVID ERDMAN SR. DIRECTOR, INVESTOR RELATIONS Agenda 9:00 ? 10:45am ET Welcome & Safe Harbor David Erdman Sr. Director, Investor Relations Opening Remarks & Company Overview Barry Biffle President & CEO Finance and Fleet Jimmy Dempsey EVP & CFO Commercial Daniel Shurz SVP, Commercial Marketing Tyri Squyres VP, Marketing Operations

Regulation FD Disclosure, Financial Statements and Exhibits

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): November 15, 2022 Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorporation) (Co

Frontier Group Holdings, Inc. Condensed Consolidated Statements of Operations (unaudited, in millions, except for per share data)

Frontier Airlines Reports Improved Profitability for the Third Quarter of 2022 DENVER - October 26, 2022 - Frontier Group Holdings, Inc.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☑ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2022 Or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number 001-40304 Frontier Group Ho

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): October 26, 2022 Frontier Group H

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): October 26, 2022 Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorporation or or

Non-Employee Director Compensation Program

Exhibit 10.1 FRONTIER GROUP HOLDINGS, INC. NON-EMPLOYEE DIRECTOR COMPENSATION PROGRAM Non-employee members of the board of directors (the ?Board?) of Frontier Group Holdings, Inc. (the ?Company?) shall be eligible to receive cash and equity compensation as set forth in this Non- Employee Director Compensation Program (this ?Program?). The cash and equity compensation described in this Program shal

Frontier Airlines Poised for Significant Growth as America’s Ultra-Low Cost Carrier Outlines Strategy to Build on Strong Foundation and Gain Share in Growing Leisure Segment Announces Unprecedented Inflation-busting Deal for Customers: One Million Se

Exhibit 99.1 Frontier Airlines Poised for Significant Growth as America?s Ultra-Low Cost Carrier Outlines Strategy to Build on Strong Foundation and Gain Share in Growing Leisure Segment Announces Unprecedented Inflation-busting Deal for Customers: One Million Seats From $19.00* Company to Release Second Quarter 2022 Financial Results After Market Close Today and Hold Conference Call at 4:30 PM ET

Eighth Amended and Restated Guarantee, dated as of June 30, 2022, by Frontier Airlines Holdings, Inc., as guarantor, in favor of Bank of Utah, not in its individual capacity but solely as security trustee.

Exhibit 10.4 CLIFFORD CHANCE US LLP EXECUTION VERSION DATED AS OF JUNE 30, 2022 FRONTIER AIRLINES HOLDINGS, INC. AS GUARANTOR AND BANK OF UTAH NOT IN ITS INDIVIDUAL CAPACITY BUT SOLELY AS SECURITY TRUSTEE EIGHTH AMENDED AND RESTATED GUARANTEE IN RESPECT OF THE PDP FINANCING OF TWENTY-ONE (21) AIRBUS A320NEO AIRCRAFT AND SIXTY-THREE (63) AIRBUS A321NEO AIRCRAFT CONTENTS Clause Page 1. Definitions 1

Amendment No. 1 to PW1100G-JM Engine Purchase and Support Agreement, dated as of April 18, 2022, by and between International Aero Engines, LLC and Frontier Airlines, Inc.

[***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10).

Second Amendment Agreement, dated as of June 30, 2022, by and among Vertical Horizons, Ltd., Bank of Utah, not in its individual capacity but solely as security trustee, and Airbus S.A.S.

[***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10).

Regulation FD Disclosure, Termination of a Material Definitive Agreement, Financial Statements and Exhibits

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): July 27, 2022 Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorporation or organ

Termination Agreement, dated as of July 27, 2022, by and among Frontier Group Holdings, Inc., Spirit Airlines, Inc. and Top Gun Acquisition Corp.

Exhibit 2.1 TERMINATION AGREEMENT THIS TERMINATION AGREEMENT (this ?Agreement?) is entered into effective as of July 27, 2022, by and among Frontier Group Holdings, Inc., a Delaware corporation (?Parent?), Top Gun Acquisition Corp., a Delaware corporation and a direct wholly owned Subsidiary of Parent (?Merger Sub?), and Spirit Airlines, Inc., a Delaware corporation (the ?Company? and, together wi

Frontier Group Holdings, Inc. Condensed Consolidated Statements of Operations (unaudited, in millions, except for per share data)

Frontier Airlines Reports Profitable Results for the Second Quarter of 2022 on a 43% Increase in Revenue over 2019 DENVER - July 27, 2022 - Frontier Group Holdings, Inc.

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): July 27, 2022 Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorporation or organ

Amendment Agreement, dated as of March 31, 2022, by and among Vertical Horizons, Ltd., Bank of Utah, not in its individual capacity but solely as security trustee, and Airbus S.A.S.

[***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10).

Third Amended and Restated IAE Engine Benefits Agreement A320neo and A321neo Aircraft (2022, 2023, 2024 and 2025 Deliveries), dated as of June 30, 2022, among Vertical Horizons, Ltd., International Aero Engines, LLC, Bank of Utah, not in its individual capacity but solely as security trustee, and Frontier Airlines, Inc.

[***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ? QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2022 Or ? TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number 001-40304 Frontier Group Holding

Eighth Amended and Restated Credit Agreement, dated as of June 30, 2022, by and among Vertical Horizons, Ltd., as borrower, Citibank, N.A., as facility agent and arranger, Bank of Utah, not in its individual capacity but solely as security trustee,

[***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10).

Amended and Restarted Guarantee, dated as of June 30, 2022, by Frontier Group Holdings, Inc., as guarantor,

[***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10).

Eighth Amended and Restated Guarantee, dated as of June 30, 2022, by Frontier Airlines, Inc., as guarantor, in favor of Bank of Utah, not in its individual capacity but solely as security trustee

Exhibit 10.3 DATED AS OF JUNE 30, 2022 FRONTIER AIRLINES INC. AS GUARANTOR AND BANK OF UTAH NOT IN ITS INDIVIDUAL CAPACITY BUT SOLELY AS SECURITY TRUSTEE EIGHTH AMENDED AND RESTATED GUARANTEE IN RESPECT OF THE PDP FINANCING OF TWENTY-ONE (21) AIRBUS A320NEO AIRCRAFT AND SIXTY-THREE (63) AIRBUS A321NEO AIRCRAFT CONTENTS Clause Page 1. Definitions 1 2. Guarantee 1 3. Guarantee Absolute 2 4. Waiver 5

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): July 11, 2022 (July 10, 2022) Fro

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): July 11, 2022 (July 10, 2022) Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorp

Financial Statements and Exhibits, Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): July 11, 2022 (July 10, 2022) Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorp

2

Exhibit 99.1 July 10, 2022 Spirit Airlines, Inc. 2800 Executive Way Miramar, FL 33025 Attention: Ted Christie; Thomas Canfield (via e-mail) Dear Ted and Thomas: On behalf of Frontier Group Holdings, Inc. (?Frontier?), I would like to reiterate our continued belief that the pending combination of Frontier with Spirit Airlines, Inc. (?Spirit?) presents a unique opportunity for both companies? stockh

Entry into a Material Definitive Agreement, Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): July 1, 2022 (June 30, 2022) Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorpo

Filed by Frontier Group Holdings, Inc.

Filed by Frontier Group Holdings, Inc. pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Spirit Airlines, Inc. SEC File No.: 001-35186 Date: June 29, 2022 The following transcript is being filed in connection with the proposed business combination of Spirit Airlines, Inc. (?Spirit?) and Frontier

Setting the Record Straight on JetBlue’s Antitrust Arguments JetBlue’s “Less Seats, Higher Prices” Acquisition Is a Dead End JetBlue’s Misdirection and Negative Attacks Cannot Hide the Fatal Flaws With its Bid to Eliminate Spirit and Derail the Front

Filed by Frontier Group Holdings, Inc. pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Spirit Airlines, Inc. SEC File No.: 001-35186 Date: June 28, 2022 The following communication is being filed in connection with the proposed business combination of Spirit Airlines, Inc. (“Spirit”) and Front

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): J une 27, 2022 (June 24, 2022) Fr

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): J une 27, 2022 (June 24, 2022) Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incor

Amendment No. 2 to Agreement and Plan of Merger, dated as of June 24, 2022, by and among Frontier Group Holdings, Inc., Spirit Airlines, Inc. and Top Gun Acquisition Corp.

Exhibit 2.1 AMENDMENT NO. 2 TO AGREEMENT AND PLAN OF MERGER This Amendment (this ?Amendment?) is made and entered into as of June 24, 2022, by and among Frontier Group Holdings, Inc., a Delaware corporation (?Parent?), Top Gun Acquisition Corp., a Delaware corporation and a direct wholly owned Subsidiary of Parent (?Merger Sub?), and Spirit Airlines, Inc., a Delaware corporation (the ?Company?). C

2

425 1 d371246d425.htm 425 Filed by Frontier Group Holdings, Inc. pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Spirit Airlines, Inc. SEC File No.: 001-35186 Date: June 27, 2022 The following letter sent to employees of Frontier Group Holdings, Inc. (“Frontier”) is being filed in connection w

Frontier Airlines Issues Open Letter to Spirit Airlines Stockholders Highlighting Greater Value and Clearer Pathway to Close Than JetBlue Proposal Leading Proxy Advisory Firms ISS and Glass Lewis Recognize Superior Long-Term Value and Upside Potentia

Filed by Frontier Group Holdings, Inc. pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Spirit Airlines, Inc. SEC File No.: 001-35186 Date: June 27, 2022 The following press release is being filed in connection with the proposed business combination of Spirit Airlines, Inc. (“Spirit”) and Front

2

425 1 d365446d425.htm 425 Filed by Frontier Group Holdings, Inc. pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Spirit Airlines, Inc. SEC File No.: 001-35186 Date: June 27, 2022 The following screenshot of a website hosted at https://EvenMoreUltraLowFares.com is being filed in connection with

Entry into a Material Definitive Agreement, Financial Statements and Exhibits

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): June 27, 2022 (June 24, 2022) Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorp

2

Filed by Frontier Group Holdings, Inc. pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Spirit Airlines, Inc. SEC File No.: 001-35186 Date: June 7, 2022 The following excerpt of an article from The Wall Street Journal, dated June 6, 2022, is being filed in connection with the proposed business

Entry into a Material Definitive Agreement, Financial Statements and Exhibits, Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): June 3, 2022 (June 2, 2022) Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorpor

2

Filed by Frontier Group Holdings, Inc. pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Spirit Airlines, Inc. SEC File No.: 001-35186 Date: June 2, 2022 The following letter sent to employees of Frontier Group Holdings, Inc. (?Frontier?) is being filed in connection with the proposed business c

Frontier Airlines and Spirit Airlines Announce Amended Merger Agreement Reverse Termination Fee of $250 Million Offers Greater Stockholder Protections

Exhibit 99.1 Frontier Airlines and Spirit Airlines Announce Amended Merger Agreement Reverse Termination Fee of $250 Million Offers Greater Stockholder Protections Denver, Colo. and Miramar, Fla., June 2, 2022 ? Spirit Airlines, Inc. (?Spirit? or the ?Company?) (NYSE: SAVE) and Frontier Group Holdings, Inc. (?Frontier?) (NASDAQ: ULCC), parent company of Frontier Airlines, Inc., today announced an

Amendment to Agreement and Plan of Merger, dated as of June 2, 2022, by and among Frontier Group Holdings, Inc., Spirit Airlines, Inc. and Top Gun Acquisition Corp.

Exhibit 2.1 AMENDMENT TO AGREEMENT AND PLAN OF MERGER This Amendment (this ?Amendment?) is made and entered into as of June 2, 2022, by and among Frontier Group Holdings, Inc., a Delaware corporation (?Parent?), Top Gun Acquisition Corp., a Delaware corporation and a direct wholly owned Subsidiary of Parent (?Merger Sub?), and Spirit Airlines, Inc., a Delaware corporation (the ?Company?). Capitali

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): June 3, 2022 (June 2, 2022) Front

425 1 d294575d425.htm 425 UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): June 3, 2022 (June 2, 2022) Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or othe

2

Filed by Frontier Group Holdings, Inc. pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Spirit Airlines, Inc. SEC File No.: 001-35186 Date: May 26, 2022 The following transcript from a session at the Wolfe Global Transportation and Industrials Conference is being filed in connection with the pr

Submission of Matters to a Vote of Security Holders

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 25, 2022 Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorporation) (Commiss

2

425 1 d300087d425.htm 425 Filed by Frontier Group Holdings, Inc. pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Spirit Airlines, Inc. SEC File No.: 001-35186 Date: May 19, 2022 The following press release is being filed in connection with the proposed business combination of Spirit Airlines,

2

425 1 d341273d425.htm 425 Filed by Frontier Group Holdings, Inc. pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Spirit Airlines, Inc. SEC File No.: 001-35186 Date: May 18, 2022 The following letter sent to employees of Frontier Group Holdings, Inc. (“Frontier”) is being filed in connection wi

Frontier Welcomes Support from Association of Flight Attendants for Spirit Transaction Combination Provides Better Opportunities and More Stability for 15,000 Professionals, Adding 10,000 Direct Jobs by 2026

Filed by Frontier Group Holdings, Inc. pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Spirit Airlines, Inc. SEC File No.: 001-35186 Date: May 17, 2022 The following press release is being filed in connection with the proposed business combination of Spirit Airlines, Inc. (“Spirit”) and Fronti

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ? QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2022 Or ? TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number 001-40304 Frontier Group Holdin

Amendment No. 1 to the Seventh Amended and Restated Credit Agreement, dated as of March 31, 2022, by and among Vertical Horizons, Ltd., Citibank, N.A., Bank of Utah and each lender identified on the signature page thereto.

[***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10).

MERGER PROPOSED?YOUR VOTE IS VERY IMPORTANT

Form 424(b)(3) Table of Contents Filed pursuant to Rule 424(b)(3) Registration No.

FRONTIER GROUP HOLDINGS, INC. 4545 Airport Way Denver, Colorado 80239

FRONTIER GROUP HOLDINGS, INC. 4545 Airport Way Denver, Colorado 80239 May 11, 2022 VIA EDGAR Division of Corporation Finance Securities and Exchange Commission 100 F Street, N.E. Washington, D.C. 20549-6010 Attention: Yolanda Guobadia, Staff Accountant Gus Rodriguez, Accounting Branch Chief Anuja Majmudar, Attorney-Advisor Laura Nicholson, Special Counsel Re: Frontier Group Holdings, Inc. Registra

Filing Fee Table.

Exhibit 107 Calculation of Filing Fee Tables Form S-4 (Form Type) Frontier Group Holdings, Inc.

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

Table of Contents 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) Delaware 4512 46-3681866 (State of Inco

Consent of Barclays Inc.

Exhibit 99.3 745 Seventh Avenue New York, NY 10019 United States May 10, 2022 CONSENT OF BARCLAYS CAPITAL INC. We hereby consent to (i) the inclusion of our opinion letter, dated February 5, 2022, to the Board of Directors of Spirit Airlines, Inc. (the ?Company?), as an Annex to the information statement and proxy statement/prospectus that forms a part of Amendment No. 3 to the Registration Statem

Consent of Citigroup Global Markets Inc.

Exhibit 99.2 CONSENT OF CITIGROUP GLOBAL MARKETS INC. We hereby consent to the use of our name and to the inclusion of our opinion letter, dated February 5, 2022, as Annex B to, and the reference thereto under the captions ?Summary?Opinion of Citigroup Global Markets Inc.,? ?The Merger?Background of the Merger,? ?The Merger?Frontier?s Reasons for the Merger,? ?The Merger?Unaudited Prospective Fina

Form of Spirit Airlines, Inc. Proxy Card.

Exhibit 99.1 SPIRIT? SPIRIT AIRLINES, INC. 2800 EXECUTIVE WAY MIRAMAR, FL 33025 VIEW MATERIALS & VOTE VOTE BY INTERNET - www.proxyvote.com or scan the QR Barcode above Use the Internet to transmit your voting instructions and for electronic delivery of information up until 11:59 p.m. Eastern Time the day before the cut-off date or meeting date. Have your proxy card in hand when you access the web

Consent of Morgan Stanley & Co. LLC

Exhibit 99.4 Consent of Morgan Stanley & Co. LLC We hereby consent to the use in Amendment No. 3 to the Registration Statement of Frontier Group Holdings Inc. on Form S-4 (the ?Registration Statement?) and in the Information Statement and Proxy Statement/Prospectus of Frontier Group Holdings Inc. and Spirit Airlines, Inc., which is part of the Registration Statement, of our opinion dated February

Consent of Morgan Stanley & Co. LLC

Exhibit 99.4 Consent of Morgan Stanley & Co. LLC We hereby consent to the use in Amendment No. 2 to the Registration Statement of Frontier Group Holdings Inc. on Form S-4 (the ?Registration Statement?) and in the Information Statement and Proxy Statement/Prospectus of Frontier Group Holdings Inc. and Spirit Airlines, Inc., which is part of the Registration Statement, of our opinion dated February

Consent of Barclays Inc.

Exhibit 99.3 745 Seventh Avenue New York, NY 10019 United States May 6, 2022 CONSENT OF BARCLAYS CAPITAL INC. We hereby consent to (i) the inclusion of our opinion letter, dated February 5, 2022, to the Board of Directors of Spirit Airlines, Inc. (the ?Company?), as an Annex to the information statement and proxy statement/prospectus that forms a part of Amendment No. 2 to the Registration Stateme

Filing Fee Table.

Exhibit 107 Calculation of Filing Fee Tables Form S-4 (Form Type) Frontier Group Holdings, Inc.

Form of Spirit Airlines, Inc. Proxy Card.

Exhibit 99.1 SPIRIT? SPIRIT AIRLINES, INC. 2800 EXECUTIVE WAY MIRAMAR, FL 33025 VIEW MATERIALS & VOTE VOTE BY INTERNET - www.proxyvote.com or scan the QR Barcode above Use the Internet to transmit your voting instructions and for electronic delivery of information up until 11:59 p.m. Eastern Time the day before the cut-off date or meeting date. Have your proxy card in hand when you access the web

As filed with the U.S. Securities and Exchange Commission on May 6, 2022

S-4/A 1 d300541ds4a.htm FORM S-4/A Table of Contents As filed with the U.S. Securities and Exchange Commission on May 6, 2022 Registration No. 333-263467 UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 AMENDMENT NO. 2 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) Delaw

Consent of Citigroup Global Markets Inc.

Exhibit 99.2 CONSENT OF CITIGROUP GLOBAL MARKETS INC. We hereby consent to the use of our name and to the inclusion of our opinion letter, dated February 5, 2022, as Annex B to, and the reference thereto under the captions ?Summary?Opinion of Citigroup Global Markets Inc.,? ?The Merger?Background of the Merger,? ?The Merger?Frontier?s Reasons for the Merger,? ?The Merger?Unaudited Prospective Fina

LETTER

United States securities and exchange commission logo May 6, 2022 Barry Biffle President and Chief Executive Officer Frontier Group Holdings, Inc.

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140 Scott Drive Menlo Park, California 94025 Tel: +1.650.328.4600 Fax: +1.650.463.2600 www.lw.com FIRM / AFFILIATE OFFICES Austin Milan Beijing Munich Boston New York Brussels Orange County Century City Paris May 5, 2022 Chicago Riyadh Dubai San Diego D?sseldorf San Francisco VIA EDGAR Frankfurt Seoul Hamburg Shanghai Hong Kong Silicon Valley Houston Singapore London Tel Aviv Los Angeles Tokyo Mad

LETTER

United States securities and exchange commission logo May 3, 2022 Barry Biffle President and Chief Executive Officer Frontier Group Holdings, Inc.

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425 1 d356924d425.htm 425 Filed by Frontier Group Holdings, Inc. pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Spirit Airlines, Inc. SEC File No.: 001-35186 Date: May 2, 2022 The following letter is being filed in connection with the proposed business combination of Spirit Airlines, Inc. (“S

Frontier Group Holdings, Inc. Condensed Consolidated Statements of Operations (unaudited, in millions, except for per share data)

EX-99.1 2 frontierearningsreleasexq.htm EX-99.1 Frontier Airlines Reports Financial Results for the First Quarter of 2022 and Expects a Return to Profitability in the Second Quarter Underpinned by Over 20% RASM Growth versus 2019 and $70 in Ancillary Revenue per Passenger DENVER - April 28, 2022 - Frontier Group Holdings, Inc. (Nasdaq: ULCC), parent company of Frontier Airlines, Inc., today report

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): April 28, 2022 Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of incorporation or orga

Filing Fee Table.

Exhibit 107 Calculation of Filing Fee Tables Form S-4 (Form Type) Frontier Group Holdings, Inc.

Consent of Barclays Inc.

EX-99.3 6 d300541dex993.htm EX-99.3 Exhibit 99.3 745 Seventh Avenue New York, NY 10019 United States April 15, 2022 CONSENT OF BARCLAYS CAPITAL INC. We hereby consent to (i) the inclusion of our opinion letter, dated February 5, 2022, to the Board of Directors of Spirit Airlines, Inc. (the “Company”), as an Annex to the information statement and proxy statement/prospectus that forms a part of Amen

Consent of Morgan Stanley & Co. LLC

Exhibit 99.4 Consent of Morgan Stanley & Co. LLC We hereby consent to the use in Amendment No. 1 to the Registration Statement of Frontier Group Holdings Inc. on Form S-4 (the ?Registration Statement?) and in the Information Statement and Proxy Statement/Prospectus of Frontier Group Holdings Inc. and Spirit Airlines, Inc., which is part of the Registration Statement, of our opinion dated February

As filed with the U.S. Securities and Exchange Commission on April 15, 2022

S-4/A 1 d300541ds4a.htm S-4/A Table of Contents As filed with the U.S. Securities and Exchange Commission on April 15, 2022 Registration No. 333-263467 UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 AMENDMENT NO. 1 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) Delawar

Consent of Citigroup Global Markets Inc.

EX-99.2 5 d300541dex992.htm EX-99.2 Exhibit 99.2 CONSENT OF CITIGROUP GLOBAL MARKETS INC. We hereby consent to the use of our name and to the inclusion of our opinion letter, dated February 5, 2022, as Annex B to, and the reference thereto under the captions “Summary—Opinion of Citigroup Global Markets Inc.,” “The Merger—Background of the Merger,” “The Merger—Frontier’s Reasons for the Merger,” “T

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140 Scott Drive Menlo Park, California 94025 Tel: +1.650.328.4600 Fax: +1.650.463.2600 www.lw.com FIRM / AFFILIATE OFFICES Austin Milan Beijing Munich Boston New York Brussels Orange County Century City Paris April 15, 2022 Chicago Riyadh Dubai San Diego Düsseldorf San Francisco Frankfurt Seoul Hamburg Shanghai VIA EDGAR Hong Kong Silicon Valley Houston Singapore London Tel Aviv Los Angeles Tokyo

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): April 14, 2022 (April 13, 2022) F

425 1 d349043d425.htm 425 UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): April 14, 2022 (April 13, 2022) Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or

Financial Statements and Exhibits, Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): April 14, 2022 (April 13, 2022) Frontier Group Holdings, Inc. (Exact name of registrant as specified in its charter) Delaware 001-40304 46-3681866 (State or other jurisdiction of inco

Frontier Airlines’ Statement Regarding HSR Second Request

Exhibit 99.1 Frontier Airlines? Statement Regarding HSR Second Request On April 13, 2022, Frontier received a request for additional information from the U.S. Department of Justice (DOJ) with respect to its proposed merger with Spirit. A second request from the DOJ was expected for a transaction of this nature ? any other airline combination would expect the same. Over the last several weeks, Fron

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A INFORMATION Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.  )

DEF 14A 1 ny20002098x1def14a.htm DEF 14A TABLE OF CONTENTS UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A INFORMATION Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.  ) Filed by the Registrant ☒ Filed by a Party other than the Registrant  ☐ Check the appropriate box:  ☐ Preliminary Proxy Statement  ☐ Confidential

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A INFORMATION Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.  )

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A INFORMATION Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.??) Filed by the Registrant ? Filed by a Party other than the Registrant ?? Check the appropriate box: ?? Preliminary Proxy Statement ?? Confidential, for Use of the Commission Only (as permitted by Rule 14a-

LETTER

United States securities and exchange commission logo April 7, 2022 Barry Biffle President and Chief Executive Officer Frontier Group Holdings, Inc.

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Filed by Frontier Group Holdings, Inc. pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Spirit Airlines, Inc. SEC File No.: 001-35186 Date: April 5, 2022 The following letter sent to employees of Frontier Group Holdings, Inc. (?Frontier?) is being filed in connection with the proposed business

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425 1 d316102d425.htm 425 Filed by Frontier Group Holdings, Inc. pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Spirit Airlines, Inc. SEC File No.: 001-35186 Date: April 5, 2022 The following statement by Frontier Group Holdings, Inc. (“Frontier”) was made publicly available regarding the pre

LETTER

United States securities and exchange commission logo April 6, 2022 James G. Dempsey Executive Vice President and Chief Financial Officer Frontier Group Holdings, Inc. 4545 Airport Way Denver, CO 80239 Re: Frontier Group Holdings, Inc. Form 10-K for Fiscal Year Ended December 31, 2021 Filed February 23, 2022 File No. 1-40304 Dear Mr. Dempsey: We have completed our review of your filing. We remind

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CORRESP 1 filename1.htm 140 Scott Drive Menlo Park, California 94025 Tel: +1.650.328.4600 Fax: +1.650.463.2600 www.lw.com FIRM / AFFILIATE OFFICES Austin Moscow Beijing Munich Boston New York Brussels Orange County Century City Paris April 1, 2022 Chicago Riyadh Dubai San Diego Düsseldorf San Francisco Frankfurt Seoul Hamburg Shanghai VIA EDGAR Hong Kong Silicon Valley Houston Singapore London Tel

LETTER

United States securities and exchange commission logo March 17, 2022 James G. Dempsey Executive Vice President and Chief Financial Officer Frontier Group Holdings, Inc. 4545 Airport Way Denver, CO 80239 Re: Frontier Group Holdings, Inc. Form 10-K for Fiscal Year Ended December 31, 2021 Filed February 23, 2022 Form 8-K Filed February 7, 2022 File No. 1-40304 Dear Mr. Dempsey: We have limited our re

FRONTIER GROUP HOLDINGS, INC. / SPIRIT AIRLINES INC. Spirit Airlines Inc. presentation delivered at the J.P. Morgan 2022 Industrials Conference on Tuesday, March 15, 2022 at 2:10 PM

Filed by Frontier Group Holdings, Inc. pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Spirit Airlines, Inc. SEC File No.: 001-35186 Date: March 16, 2022 The following transcript of a presentation on March 15, 2022 is being filed in connection with the proposed business combination of Spirit A

Filed by Frontier Group Holdings, Inc.

Filed by Frontier Group Holdings, Inc. pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Spirit Airlines, Inc. SEC File No.: 001-35186 Date: March 15, 2022 The following presentation is being filed in connection with the proposed business combination of Spirit Airlines, Inc. (?Spirit?) and Front

Consent of Morgan Stanley & Co. LLC

Exhibit 99.4 Consent of Morgan Stanley & Co. LLC We hereby consent to the use in the Registration Statement of Frontier Group Holdings Inc. on Form S-4 (the “Registration Statement”) and in the Information Statement and Proxy Statement/Prospectus of Frontier Group Holdings Inc. and Spirit Airlines, Inc., which is part of the Registration Statement, of our opinion dated February 5, 2022 appearing a

Consent of Barclays Inc.

EX-99.3 6 d300541dex993.htm EX-99.3 Exhibit 99.3 745 Seventh Avenue New York, NY 10019 United States March 11, 2022 CONSENT OF BARCLAYS CAPITAL INC. We hereby consent to (i) the inclusion of our opinion letter, dated February 5, 2022, to the Board of Directors of Spirit Airlines, Inc. (the “Company”), as an Annex to the information statement and proxy statement/prospectus that forms a part of the

Consent of Citigroup Global Markets Inc.

Exhibit 99.2 CONSENT OF CITIGROUP GLOBAL MARKETS INC. We hereby consent to the use of our name and to the inclusion of our opinion letter, dated February 5, 2022, as Annex B to, and the reference thereto under the captions ?Summary?Opinion of Citigroup Global Markets Inc.,? ?The Merger?Background of the Merger,? ?The Merger?Frontier?s Reasons for the Merger,? ?The Merger?Unaudited Prospective Fina

Powers of Attorney.

Table of Contents As filed with the U.S. Securities and Exchange Commission on March 11, 2022 Registration No. 333- UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM S-4 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 Frontier Group Holdings, Inc. (Exact Name of Registrant as Specified in Its Charter) Delaware 4512 46-3681866 (State of Incorporation) (Primary Sta

Filing Fee Table.

Exhibit 107 Calculation of Filing Fee Tables Form S-4 (Form Type) Frontier Group Holdings, Inc.

FRONTIER GROUP HOLDINGS, INC. (ULCC) March 9, 2022 | Raymond James 43rd Institutional Investors Conference

425 1 d280502d425.htm 425 Filed by Frontier Group Holdings, Inc. pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Spirit Airlines, Inc. SEC File No.: 001-35186 Date: March 9, 2022 The following transcript of a webcast on March 9, 2022 is being filed in connection with the proposed business comb

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425 1 d684147d425.htm 425 Filed by Frontier Group Holdings, Inc. pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Spirit Airlines, Inc. SEC File No.: 001-35186 Date: February 25, 2022 The following screenshot of an updated Q&A on the website hosted at https://EvenMoreUltraLowFares.com is being

Barclays Industrial Select Conference

425 1 d160224d425.htm 425 Filed by Frontier Group Holdings, Inc. pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Spirit Airlines, Inc. SEC File No.: 001-35186 Date: February 25, 2022 The following transcript is being filed in connection with the proposed business combination of Spirit Airlines

Third Amended and Restated Letter Agreement No. 2, dated as of November 13, 2021, by and between Airbus S.A.S. and Frontier Airlines, Inc.

[***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10).

Seventh Amended and Restated Credit Agreement, dated as of December 28, 2021, by and among Vertical Horizons, Ltd., Citibank, N.A., Bank of Utah and each lender identified on Schedule I thereto.

[***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10).

Seventh Amended and Restated Guarantee, dated as of December 28, 2021, by Frontier Airlines, Inc. in favor of Bank of Utah.

Exhibit 10.26 CLIFFORD CHANCE US LLP EXECUTION VERSION DATED AS OF DECEMBER 28, 2021 FRONTIER AIRLINES INC. AS GUARANTOR AND BANK OF UTAH NOT IN ITS INDIVIDUAL CAPACITY BUT SOLELY AS SECURITY TRUSTEE SEVENTH AMENDED AND RESTATED GUARANTEE IN RESPECT OF THE PDP FINANCING OF NINE (9) AIRBUS A320NEO AIRCRAFT AND FIFTY (50) AIRBUS A321NEO AIRCRAFT 24002499643-v4 80-40605773 CONTENTS Clause Page 1. Def

Seventh Amended and Restated Guarantee, dated as of December 28, 2021, by Frontier Airlines Holdings, Inc. in favor of Bank of Utah.

Exhibit 10.27 CLIFFORD CHANCE US LLP EXECUTION VERSION DATED AS OF DECEMBER 28, 2021 FRONTIER AIRLINES HOLDINGS, INC. AS GUARANTOR AND BANK OF UTAH NOT IN ITS INDIVIDUAL CAPACITY BUT SOLELY AS SECURITY TRUSTEE SEVENTH AMENDED AND RESTATED GUARANTEE IN RESPECT OF THE PDP FINANCING OF NINE (9) AIRBUS A320NEO AIRCRAFT AND FIFTY (50) AIRBUS A321NEO AIRCRAFT 24002493669-v4 80-40605773 CONTENTS Clause P

Letter Agreement No. 11, dated as of November 13, 2021, by and between Airbus S.A.S. and Frontier Airlines, Inc.

[***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10).

Amended and Restated Step-In Agreement, dated as of December 28, 2021 by and among Vertical Horizons, Ltd., Bank of Utah and Airbus S.A.S.

[***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10).