| Item 1. | |
| (a) | Name of issuer:
Sun Country Airlines Holdings, Inc. |
| (b) | Address of issuer's principal executive offices:
2005 CARGO ROAD, MINNEAPOLIS, Minnesota, 55450 |
| Item 2. | |
| (a) | Name of person filing:
Zimmer Partners, LP, a Delaware limited partnership (the "Investment Manager"), Zimmer Financial Services Group LLC, a Delaware limited liability company ("ZFSG"), Zimmer Partners GP, LLC, a Delaware limited liability company (the "GP"), and Stuart J. Zimmer (collectively, the "Reporting Persons"). ZFSG is the sole member of the GP. Stuart J. Zimmer, a revocable trust for his benefit, and an irrevocable trust for his immediate family are the sole members of ZFSG. The GP is the general partner of the Investment Manager. The Investment Manager is the investment manager of ZP Master Utility Fund, Ltd. and ZP Master MidCap Fund, Ltd. and certain separately managed accounts. |
| (b) | Address or principal business office or, if none, residence:
The address of the principal business office of each of the Reporting Persons is c/o Zimmer Partners, LP, 9 West 57th Street, 33rd Floor
New York, NY 10019. |
| (c) | Citizenship:
Delaware |
| (d) | Title of class of securities:
Common Stock, par value $0.01 per share |
| (e) | CUSIP No.:
866683105 |
| Item 3. | If this statement is filed pursuant to §§ 240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a: |
| (a) |  Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o);
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| (b) | Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c);
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| (c) | Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c);
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| (d) | Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8);
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| (e) |  An investment adviser in accordance with § 240.13d-1(b)(1)(ii)(E);
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| (f) | An employee benefit plan or endowment fund in accordance with § 240.13d-1(b)(1)(ii)(F);
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| (g) | A parent holding company or control person in accordance with § 240.13d-1(b)(1)(ii)(G);
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| (h) | A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);
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| (i) | A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);
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| (j) | A non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J). If filing as a non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J),
please specify the type of institution:
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| (k) | Group, in accordance with Rule 240.13d-1(b)(1)(ii)(K).
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| | |
| Item 4. | Ownership |
| (a) | Amount beneficially owned:
The Reporting Persons may be deemed the beneficial owners of 2,225,900 shares of Common Stock. The Reporting Persons may be deemed the beneficial owners of approximately 4.2% of the outstanding shares of Common Stock. This percentage was determined by dividing 2,225,900 by 53,316,378, which is the number of shares of Common Stock outstanding as of June 30, 2025, as reported in the Issuer's Form 10-Q filed on August 1, 2025 with the Securities and Exchange Commission. The Reporting Persons have the shared power to vote and dispose of the 2,225,900 shares of Common Stock beneficially owned. |
| (b) | Percent of class:
4.2% |
| (c) | Number of shares as to which the person has:
|
| | (i) Sole power to vote or to direct the vote:
0
|
| | (ii) Shared power to vote or to direct the vote:
2,225,900
|
| | (iii) Sole power to dispose or to direct the disposition of:
0
|
| | (iv) Shared power to dispose or to direct the disposition of:
2,225,900
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| Item 5. | Ownership of 5 Percent or Less of a Class. |
| |
Ownership of 5 percent or less of a class
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| Item 6. | Ownership of more than 5 Percent on Behalf of Another Person. |
| |
Not Applicable
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| Item 7. | Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person. |
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Not Applicable
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| Item 8. | Identification and Classification of Members of the Group. |
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Not Applicable
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| Item 9. | Notice of Dissolution of Group. |
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Not Applicable
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