UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K

(Mark One)

For the fiscal year ended December 31, 2015

or

For the transition period from                      to                     

Commission file number of the issuing entity: 333-171508-01

Central Index Key Number of the issuing entity: 0001530219

GS Mortgage Securities Trust 2011-GC5

(exact name of the issuing entity as specified in its charter)

Central Index Key Number of the depositor: 0001004158

GS Mortgage Securities Corporation II

(exact name of the depositor as specified in its charter)

Central Index Key Number of the sponsor: 0001541502

Goldman Sachs Mortgage Company

(exact name of the sponsor as specified in its charter)

Central Index Key Number of the sponsor: 0001541001

Citigroup Global Markets Realty Corp.

(exact name of the sponsor as specified in its charter)

c/o Citibank, N.A.

as Certificate Administrator

388 Greenwich Street, 14th Floor

New York, NY

(Address of principal executive offices of the issuing entity)

10013

(Zip Code)

Registrant’s telephone number, including area code:

(212) 902-1000

Securities registered pursuant to Section 12(b) of the Act: None.

Securities registered pursuant to Section 12(g) of the Act: None.

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.    ¨  Yes    x  No

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act.    ¨  Yes    x  No

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.    x  Yes    ¨  No

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T (Section 232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files).

Not applicable.

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K (Section 229.405 of this chapter) is not contained herein, and will not be contained, to the best of registrant’s knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K.

Not applicable.

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

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act).    ¨  Yes    x  No

State the aggregate market value of the voting and non-voting common equity held by non-affiliates computed by reference to the price at which the common equity was last sold, or the average bid and asked price of such common equity, as of the last business day of the registrant’s most recently completed second fiscal quarter.

Not applicable.

Indicate by check mark whether the registrant has filed all documents and reports required to be filed by Section 12, 13 or 15(d) of the Securities Exchange Act of 1934 subsequent to the distribution of securities under a plan confirmed by a court.    ¨  Yes    ¨  No

Not applicable.

Indicate the number of shares outstanding of each of the registrant’s classes of common stock, as of the latest practicable date.

Not applicable.

DOCUMENTS INCORPORATED BY REFERENCE

List hereunder the following documents if incorporated by reference and the Part of the Form 10-K (e.g., Part I, Part II, etc.) into which the document is incorporated: (1) Any annual report to security holders; (2) Any proxy or information statement; and (3) Any prospectus filed pursuant to Rule 424(b) or (c) under the Securities Act of 1933. The listed documents should be clearly described for identification purposes (e.g., annual report to security holders for fiscal year ended December 24, 1980).

Not applicable.

EXPLANATORY NOTES

Deutsche Bank Trust Company Americas (as successor to Deutsche Bank National Trust Company) acts as trustee of the mortgage loans serviced under the Pooling and Servicing Agreement. The trustee is required to provide an assessment of compliance with applicable servicing criteria solely with respect to Item 1122(d)(2)(iii) of Regulation AB (regarding advances of funds or guarantees regarding collections, cash flows or distributions, and any interest or other fees charged for such advances, are made, reviewed and approved as specified in the transaction agreements). However, during the reporting period, the trustee did not perform any servicing function with respect to the servicing criteria specified in Item 1122(d)(2)(iii). The master servicer or the special servicer, to the extent required, performed the servicing function identified with respect to Item 1122(d)(2)(iii), and each such party included Item 1122(d)(2)(iii) in the assessment of compliance with applicable servicing criteria and accountant’s attestation report for the subject transaction. As a result, consistent with industry practice, this Annual Report on Form 10-K does not include an assessment of compliance with applicable servicing criteria of the trustee.

Torchlight Loan Services, LLC (“Torchlight”) acted as special servicer of the mortgage loans serviced under the Pooling and Servicing Agreement prior to January 23, 2015, the date as of which Torchlight was removed as special servicer and replaced by LNR Partners, LLC (“LNR”). LNR is the special servicer of the mortgage loans serviced under the Pooling and Servicing Agreement on and after January 23, 2015. In accordance with the Compliance and Disclosure Interpretations, Section 200.03 (Rules 13a-18 and 15d-18, Servicer’s Assessment of Compliance), the percentage set forth above must be reduced for each special servicer pro rata because each was only acting as a special servicer of mortgage loans serviced under the Pooling and Servicing Agreement for a portion of the reporting period covered by this Annual Report on Form 10-K. As a result, Torchlight falls below the de minimis requirements in Item 1123 of Regulation AB and no servicer compliance statements for Torchlight is required.

This Annual Report on Form 10-K includes an assessment of compliance with applicable servicing criteria and an accountant’s attestation report from U.S. Bank, National Association. This entity was engaged by the Certificate Administrator to perform certain custodial services. These services are included within the servicing criteria set forth in Items 1122(d)(4)(i) and 1122(d)(4)(ii). Therefore, under the principles-based definition of “servicer” set forth in Item 1101(j) that looks to the functions that an entity performs, this vendor is a “servicer” for the purposes of Item 1122. See Compliance and Disclosure Interpretations, Section 301.01 (Item 1101(j)).

This Annual Report on Form 10-K includes assessments of compliance with applicable servicing criteria and accountants’ attestation reports from CoreLogic Commercial Real Estate Services, Inc. and National Tax Search, LLC. These entities were engaged by the master servicer of the Pooling and Servicing Agreement to remit tax payments received from the escrow accounts of borrowers to local taxing authorities, to report tax amounts due, to verify tax parcel information, and to verify non-escrow tax payments. These services are included within the servicing criteria set forth in Items 1122(d)(4)(xi) and 1122(d)(4)(xii). Therefore, under the principles-based definition of “servicer” set forth in Item 1101(j) that looks to the functions that an entity performs, these vendors are “servicers” for the purposes of Item 1122. See Compliance and Disclosure Interpretations, Section 301.01 (Item 1101(j)).

PART I

Omitted.

Omitted.

None.

Omitted.

Omitted.

Not applicable.

PART II

Omitted.

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Omitted.

Omitted.

Omitted.

Omitted.

Omitted.

Omitted.

None.

PART III

Omitted.

Omitted.

Omitted.

Omitted.

Omitted.

ADDITIONAL DISCLOSURE ITEMS FOR REGULATION AB

Item 1112(b) of Regulation AB, Significant Obligor Financial Information.

The Park Place Mall Mortgage Loan (Control Number 1 on Annex A of the prospectus supplement of the registrant relating to the issuing entity filed on October 11, 2011 pursuant to Rule 424(b)(5)) constitutes a significant obligor within the meaning of Item 1101(k)(2) of Regulation AB as disclosed in the prospectus supplement. In accordance with Item 1112(b) of Regulation AB, the most recent unaudited net operating income of the significant obligor was $20,825,443.00 for the twelve- month period ended December 31, 2015.

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The 1551 Broadway Mortgage Loan (Control Number 2 on Annex A of the prospectus supplement of the registrant relating to the issuing entity filed on October 11, 2011 pursuant to Rule 424(b)(5)) constitutes a significant obligor within the meaning of Item 1101(k)(2) of Regulation AB. In accordance with Item 1112(b) of Regulation AB, the most recent unaudited net operating income of the significant obligor was $17,431,139.00 for the twelve- month period ended December 31, 2015.

American Eagle Outfitters, Inc., the guarantor of the lease of the sole tenant at the mortgaged property that secures the 1551 Broadway mortgage loan (Control Number 2 on Annex A to the prospectus supplement of the Registrant relating to the issuing entity filed on October 11, 2011 pursuant to Rule 424(b)(5)), constitutes a significant obligor within the meaning of Item 1101(k)(1) of Regulation AB. Set forth in the table below is the information required under Item 1112(b) of Regulation AB with respect to such significant obligor which was previously reported on such significant obligor’s Form 10-K filed on March 10, 2016, Accession Number 0001564590-16-014422:

Item 1114(b)(2) of Regulation AB, Significant Enhancement Provider Financial Information.

No entity or group of affiliated entities provides any external credit enhancement or other support for the certificates within this transaction as described under Item 1114(a) of Regulation AB.

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Item 1115(b) of Regulation AB, Certain Derivatives Instruments (Financial Information).

No entity or group of affiliated entities provides any derivative instruments or other support for the certificates within this transaction as described under Item 1115 of Regulation AB.

Item 1117 of Regulation AB, Legal Proceedings.

The registrant knows of no material pending legal proceeding involving the trust or any party related to the trust, other than routine litigation incidental to the duties of those respective parties, and the following, with respect to Deutsche Bank Trust Company Americas (as successor to Deutsche Bank National Trust Company), as trustee, Citibank, N.A., as certificate administrator, and U.S. Bank National Association, as custodian:

On June 18, 2014, a group of investors, including funds managed by Blackrock Advisors, LLC, PIMCO-Advisors, L.P., and others, filed a derivative action against Deutsche Bank Trust Company Americas (“DBTCA”) and Deutsche Bank National Trust Company (“DBNTC”) in New York State Supreme Court purportedly on behalf of and for the benefit of 544 private-label RMBS trusts asserting claims for alleged violations of the U.S. Trust Indenture Act of 1939 (TIA), breach of contract, breach of fiduciary duty and negligence based on DBNTC and DBTCA’s alleged failure to perform their duties as trustees for the trusts. Plaintiffs subsequently dismissed their state court complaint and filed a derivative and class action complaint in the U.S. District Court for the Southern District of New York on behalf of and for the benefit of 564 private-label RMBS trusts, which substantially overlapped with the trusts at issue in the state court action. The complaint alleges that the trusts at issue have suffered total realized collateral losses of U.S. $89.4 billion, but the complaint does not include a demand for money damages in a sum certain. DBNTC and DBTCA filed a motion to dismiss, and on January 19, 2016, the court partially granted the motion on procedural grounds: as to the 500 trusts that are governed by Pooling and Servicing Agreements, the court declined to exercise jurisdiction. The court did not rule on substantive defenses asserted in the motion to dismiss as to the 64 trusts formed under indentures for which it retained jurisdiction. Instead, the court ordered plaintiffs to file an amended complaint as to those indenture trusts. On February 23, 2016, plaintiffs filed an amended complaint as to 62 of the 64 indenture trusts included in the original U.S. District Court complaint. DBNTC and DBTCA will have an opportunity to file new defensive motions with respect to this amended complaint. It is anticipated that plaintiffs will, in the near future, file a new state court complaint as to some or all of the 500 trusts governed by Pooling and Servicing Agreements which were dismissed from the U.S. District Court action.

On December 30, 2015, IKB International, S.A. and IKB Deutsche Industriebank A.G. filed a Summons With Notice in New York state court naming as defendants DBNTC and DBTCA, as trustees of 37 RMBS trusts (the “IKB Action”). The claims in the IKB Action appear to be substantively similar to the SDNY Action. The IKB Action is not styled as a putative class action, but may attempt to bring derivative claims on behalf of the named RMBS Trusts. DBTCA intends to vigorously defend the IKB Action.

DBTCA has no pending legal proceedings (including, based on DBTCA’s present evaluation, the litigation disclosed in the foregoing paragraphs) that would materially affect its ability to perform its duties as Trustee under the Pooling and Servicing Agreement for this transaction.

On June 18, 2014, a civil action was filed against Citibank, N.A. (“Citibank”) in the Supreme Court of the State of New York by a group of investors in 48 private-label RMBS trusts for which Citibank allegedly serves or did serve as trustee, asserting claims for purported violations of the Trust Indenture Act of 1939, breach of contract, breach of fiduciary duty and negligence based on Citibank’s alleged failure to perform its duties as trustee for the 48 RMBS trusts. On November 24, 2014, plaintiffs sought leave to withdraw this action. On the same day, a smaller subset of similar plaintiff investors in 27 private-label RMBS trusts for which Citibank allegedly serves or did serve as trustee, filed a new civil action against Citibank in the United States District Court for the Southern District of New York asserting similar claims as the prior action filed in state court. In January 2015, the court closed plaintiffs’ original state court action. Citibank’s motion to dismiss the federal complaint was fully briefed as of May 13, 2015. On September 8, 2015, the federal court dismissed all claims as to 24 of the 27 trusts and allowed certain of the claims to proceed as to the other three trusts. That case, involving the three remaining trusts, is pending.

On November 24, 2015, the same investors that brought the federal case brought a new civil action in the Supreme Court of the State of New York related to 25 private-label RMBS trusts for which Citibank allegedly serves or did serve as trustee. This case includes the 24 trusts previously dismissed in the federal action, and one additional trust. The investors assert claims for breach of contract, breach of fiduciary duty, breach of duty to avoid conflicts of interest, and violation of New York’s Streit Act. Citibank filed a motion to dismiss this case on February 26, 2016.

On August 19, 2015, the Federal Deposit Insurance Corporation (“FDIC”) as Receiver for a financial institution filed a civil action against Citibank in the Southern District of New York. This action relates to one private-label RMBS trust for which Citibank formerly served as trustee. FDIC asserts claims for breach of contract, violation of the Streit Act, and violation of the Trust Indenture Act. Citibank is jointly briefing a motion to dismiss with The Bank of New York Mellon and U.S. Bank, entities that have also been sued by FDIC in their capacity as trustee, and whose cases are all in front of Judge Carter.

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There can be no assurances as to the outcome of litigation or the possible impact of litigation on the trustee or the RMBS trusts. However, Citibank denies liability and continues to vigorously defend against these litigations. Furthermore, neither the above-disclosed litigations nor any other pending legal proceeding involving Citibank will materially affect Citibank’s ability to perform its duties as Certificate Administrator under the Pooling and Servicing Agreement for this CMBS transaction.

Since 2014 various plaintiffs or groups of plaintiffs, primarily investors, have filed claims against U.S. Bank National Association (“U.S. Bank”), in its capacity as trustee or successor trustee (as the case may be) under certain residential mortgage backed securities (“RMBS”) trusts. The plaintiffs or plaintiff groups have filed substantially similar complaints against other RMBS trustees, including Deutsche Bank, Citibank, HSBC, Bank of New York Mellon and Wells Fargo. The complaints against U.S. Bank allege the trustee caused losses to investors as a result of alleged failures by the sponsors, mortgage loan sellers and servicers for these RMBS trusts and assert causes of action based upon the trustee’s purported failure to enforce repurchase obligations of mortgage loan sellers for alleged breaches of representations and warranties concerning loan quality. The complaints also assert that the trustee failed to notify securityholders of purported events of default allegedly caused by breaches of servicing standards by mortgage loan servicers and that the trustee purportedly failed to abide by a heightened standard of care following alleged events of default.

Currently U.S. Bank is a defendant in multiple actions alleging individual or class action claims against the trustee with respect to multiple trusts as described above with the most substantial case being: BlackRock Balanced Capital Portfolio et al v. U.S. Bank National Association, No. 605204/2015 (N.Y. Sup. Ct.) (class action alleging claims with respect to approximately 794 trusts) and its companion case BlackRock Core Bond Portfolio et al v. U.S Bank National Association, No. 14-cv-9401 (S.D.N.Y.). Some of the trusts implicated in the aforementioned Blackrock cases, as well as other trusts, are involved in actions brought by separate groups of plaintiffs related to no more than 100 trusts per case.

There can be no assurance as to the outcome of any of the litigation, or the possible impact of these litigations on the trustee or the RMBS trusts. However, U.S. Bank denies liability and believes that it has performed its obligations under the RMBS trusts in good faith, that its actions were not the cause of losses to investors and that it has meritorious defenses, and it intends to contest the plaintiffs’ claims vigorously.

Item 1119 of Regulation AB, Affiliations and Certain Relationships and Related Transactions.

The information regarding this Item has been previously provided in a prospectus supplement of the Registrant relating to the issuing entity filed on October 11, 2011 pursuant to Rule 424(b)(5).

Item 1122 of Regulation AB, Compliance with Applicable Servicing Criteria.

The reports on assessments of compliance with the servicing criteria for asset-backed securities and related attestation reports on such assessments of compliance with respect to the mortgage loans are attached hereto under Item 15 to this Annual Report on Form 10-K. Attached as Exhibit O to the Pooling and Servicing Agreement incorporated by reference as Exhibit 4 to this Annual Report on Form 10-K is a chart identifying the entities participating in a servicing function for the transaction responsible for each applicable servicing criteria set forth in Item 1122(d).

Item 1123 of Regulation AB, Servicer Compliance Statement.

The servicer compliance statements are attached as Exhibits to this Annual Report on Form 10-K.

PART IV

Item 15. Exhibits, Financial Statement Schedules

(a) The following is a list of documents filed as part of this Annual Report on Form 10-K:

(1) Not applicable

(2) Not applicable

(3) See below

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(b) The exhibits required to be filed by the Registrant pursuant to Item 601 of Regulation S-K are listed above and in the Exhibit Index that immediately follows the signature page hereof.

(c) Not Applicable.

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SIGNATURES

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

Exhibit Index

Exhibit No.

8

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