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SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

SCHEDULE 13D

(Rule 13d-101. Information to be Included in Statements Filed Pursuant to § 240.13d-1(a) and Amendments Thereto Filed Pursuant to § 240.13d-2(a))

Under the Securities Exchange Act of 1934

(Amendment No. 5)*

Six Flags Entertainment Corporation

(Name of Issuer)

Common Stock, par value $0.025

(Title of Class of Securities)

83001A 102

83001A 201

(CUSIP Number)

H Partners Management, LLC

888 Seventh Avenue

29th Floor

New York, New York 10019

Attn: Rehan Jaffer

(212) 265-4200

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

January 30, 2014

(Date of Event which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box  ¨.

Note. Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See §240.13d-7 for other parties to whom copies are to be sent.

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

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13D

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13D

The Statement on Schedule 13D, as originally filed with the Securities and Exchange Commission on May 10, 2010 (the “Schedule 13D”) by the Reporting Persons named therein is hereby further amended and supplemented by this Amendment No. 5 to Schedule 13D. Capitalized terms used herein and not otherwise defined have the meanings assigned to such terms in the Schedule 13D.

The information set forth in response to each separate Item below shall be deemed to be a response to all Items where such information is relevant. The Schedule 13D is hereby amended as follows:

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13D

Item 4. Purpose of Transaction.

Item 4 is hereby amended and restated in its entirety as follows:

The Reporting Persons played a leading role in recapitalizing the Issuer during the Issuer’s bankruptcy proceedings in 2009 and 2010. In connection with the Issuer’s recapitalization in 2010, the Reporting Persons established Special Purpose Vehicles (“SPVs”) separate from the Reporting Person’s main funds. Upon the SPVs’ expiration, the Reporting Persons distributed 7,393,652 shares of common stock to the SPVs’ underlying limited partners and ceased serving as investment manager of a fund which directly owned 1,732,306 shares of common stock. As a result, the Reporting Persons may no longer be deemed to have voting or dispositive power with respect to such shares of common stock. The Reporting Persons intend to hold approximately 16.4 million shares of common stock, representing its entire remaining stake. The Reporting Persons continue to be optimistic about the Issuer’s prospects.

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13D

Item 5. Interest in Securities of the Issuer.

Item 5 is hereby amended and restated in its entirety as follows:

The information set forth in Item 4 of this Statement is hereby incorporated by reference into this Item 5. As of January 30, 2014, the Reporting Persons beneficially own an aggregate of 16,419,438 shares of Common Stock, or approximately 17.3% of the Common Stock then outstanding as of October 25, 2013. These shares of Common Stock include shares of Common Stock received by the H Partners Entities in connection with the Issuer’s emergence from bankruptcy and subsequently transferred between investment funds, and shares of Common Stock transferred to investment funds that are managed by H Management.

(a) and (b)

1) H LP directly beneficially owns 9,107,778 shares of Common Stock, constituting approximately 9.6% of the Common Stock outstanding. As of the date of this filing, H LP has sole voting power and sole investment power with respect to all the shares of Common Stock referred to in the previous sentence.

2) H Capital, as the general partner of H LP, may be deemed to beneficially own 9,107,778 shares of Common Stock, constituting approximately 9.6% of the Common Stock. H Capital may be deemed to have sole voting power and sole investment power with respect to all the shares of Common Stock referred to in the previous sentence.

3) H Management, as the investment manager of H Capital and Phoenix Capital, may be deemed to beneficially own 16,419,438 shares of Common Stock, constituting approximately 17.3% of the Common Stock. H Management may be deemed to have sole voting power and sole investment power with respect to all the shares of Common Stock referred to in the previous sentence.

4) Jaffer, as the managing member of H Management, H Capital and Phoenix Capital, may be deemed to beneficially own 16,419,438 shares of Common Stock, constituting approximately 17.3% of the Common Stock. Jaffer may be deemed to have sole voting power and sole investment power with respect to all the shares of Common Stock referred to in the previous sentence.

Neither the filing of this Statement nor any of its contents shall be deemed to constitute an admission that any Reporting Person are the beneficial owner of any Common Stock referred to in this Statement for the purposes of Section 13(d) of the Act or for any other purpose, and such beneficial ownership is expressly disclaimed.

(c) Except as stated in Item 3 and Item 4 herein, there have been no other transactions in the securities of the Issuer effected by the Reporting Persons in the last 60 days.

(d) Except as stated within Item 4 and Item 5 of this Statement, to the knowledge of the Reporting Persons, only the Reporting Persons have the right to receive or the power to direct the receipt of dividends from, or proceeds from the sale of, the shares of Common Stock of the Issuer reported by this Statement.

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13D

Item 7. Material to be Filed as Exhibits.

Item 7 is hereby amended and restated in its entirety as follows:

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SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Date: February 3, 2014

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Index of Exhibits

Exhibit 99.1

Joint Filing Agreement

The undersigned hereby agree as follows:

Date: February 3, 2014