UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K

For the fiscal year ended December 31, 2013

or

For the transition period from                      to                     

333-185882-04

(Commission File Number of issuing entity)

Sequoia Mortgage Trust 2013-8

(Exact name of issuing entity as specified in its charter)

333-185882-01

(Commission File Number of depositor)

Sequoia Residential Funding, Inc.

(Exact name of depositor as specified in its charter)

RWT Holdings, Inc.

(Exact name of sponsor as specified in its charter)

New York

(State or other jurisdiction of incorporation or organization of the issuing entity)

46-3062396

46-3072712

(I.R.S. Employer Identification No.)

(212) 816-5693

(Telephone number, including area code)

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 (§ 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 (§ 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 the 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.

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

PART I

Item 1. Business.

Omitted.

Item 1A. Risk Factors.

Omitted.

Item 1B. Unresolved Staff Comments.

None.

Item 2. Properties.

Omitted.

Item 3. Legal Proceedings.

Omitted.

Item 4. Mine Safety Disclosures.

Omitted.

PART II

Item 5. Market for Registrant’s Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities.

Omitted.

Item 6. Selected Financial Data.

Omitted.

Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations.

Omitted.

Item 7A. Quantitative and Qualitative Disclosures About Market Risk.

Omitted.

Item 8. Financial Statements and Supplementary Data.

Omitted.

Item 9. Changes in and Disagreements With Accountants on Accounting and Financial Disclosure.

Omitted.

Item 9A. Controls and Procedures.

Omitted.

Item 9B. Other Information.

None.

PART III

Item 10. Directors, Executive Officers and Corporate Governance.

Omitted.

Item 11. Executive Compensation.

Omitted.

Item 12. Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters.

Omitted.

Item 13. Certain Relationships and Related Transactions, and Director Independence.

Omitted.

Item 14. Principal Accounting Fees and Services.

Omitted.

ADDITIONAL DISLCOSURE ITEMS REQUIRED BY GENERAL INSTRUCTION J(2)

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

No single obligor represents 10% or more of the pool assets held by the issuing entity.

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.

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.

On or about December 23, 2009, the Federal Home Loan Bank of Seattle (the “FHLB-Seattle”) filed a complaint in the Superior Court for the State of Washington (case number 09-2-46348-4 SEA) against Redwood Trust, Inc., our subsidiary, Sequoia Residential Funding, Inc. (“SRF”), Morgan Stanley & Co., and Morgan Stanley Capital I, Inc. (collectively, the “FHLB-Seattle Defendants”) alleging that the FHLB-Seattle Defendants made false or misleading statements in offering materials for a mortgage pass-through certificate (the “Seattle Certificate”) issued in the Sequoia Mortgage Trust 2005-4 securitization transaction (the “2005-4 RMBS”) and purchased by the FHLB-Seattle. Specifically, the complaint alleges that the alleged misstatements concern the (1) loan-to-value ratio of mortgage loans and the appraisals of the properties that secured loans supporting the 2005-4 RMBS, (2) occupancy status of the properties, (3) standards used to underwrite the loans, and (4) ratings assigned to the Seattle Certificate. The FHLB-Seattle alleges claims under the Securities Act of Washington (Section 21.20.005, et seq.) and seeks to rescind the purchase of the Seattle Certificate and to collect interest on the original purchase price at the statutory interest rate of 8% per annum from the date of original purchase (net of interest received) as well as attorneys’ fees and costs. The Seattle Certificate was issued with an original principal amount of approximately $133 million, and, as of December 31, 2013, the FHLB-Seattle has received approximately $114.4 million of principal and $11.0 million of interest payments in respect of the Seattle Certificate. As of December 31, 2013, the Seattle Certificate had a remaining outstanding principal amount of approximately $19.0 million. The claims were subsequently dismissed for lack of personal jurisdiction as to Redwood Trust and SRF. Redwood agreed to indemnify the underwriters of the 2005-4 RMBS for certain losses and expenses they might incur as a result of claims made against them relating to this RMBS, including, without limitation, certain legal expenses. The FHLB-Seattle’s claims against the underwriters of this RMBS were not dismissed and remain pending. Regardless of the outcome of this litigation, Redwood could incur a loss as a result of these indemnities.

On or about July 15, 2010, The Charles Schwab Corporation (“Schwab”) filed a complaint in the Superior Court for the State of California in San Francisco (case number CGC-10-501610) against SRF and 26 other defendants (collectively, the “Schwab Defendants”) alleging that the Schwab Defendants made false or misleading statements in offering materials for various residential mortgage-backed securities sold or issued by the Schwab Defendants. With respect to SRF, Schwab alleges that SRF made false or misleading statements in offering materials for a mortgage pass-through certificate (the “Schwab Certificate”) issued in the 2005-4 RMBS and purchased by Schwab. Specifically, the complaint alleges that the misstatements for the 2005-4 RMBS concern the (1) loan-to-value ratio of mortgage loans and the appraisals of the properties that secured loans supporting the 2005-4 RMBS, (2)

occupancy status of the properties, (3) standards used to underwrite the loans, and (4) ratings assigned to the Schwab Certificate. Schwab alleges a claim for negligent misrepresentation under California state law and seeks unspecified damages and attorneys’ fees and costs. The Schwab Certificate was issued with an original principal amount of approximately $14.8 million, and, as of December 31, 2013, Schwab has received approximately $12.7 million of principal and $1.3 million of interest payments in respect of the Schwab Certificate. As of December 31, 2013, the Schwab Certificate had a remaining outstanding principal amount of approximately $2.1 million. SRF has denied Schwab’s allegations. We intend to defend the action vigorously. Redwood agreed to indemnify the underwriters of the 2005-4 RMBS, which underwriters are also named defendants in this action, for certain losses and expenses they might incur as a result of claims made against them relating to this RMBS, including, without limitation, certain legal expenses. Regardless of the outcome of this litigation, Redwood could incur a loss as a result of these indemnities.

On or about October 15, 2010, the Federal Home Loan Bank of Chicago (“FHLB-Chicago”) filed a complaint in the Circuit Court of Cook County, Illinois (case number 10-CH-45033) against SRF and more than 45 other named defendants (collectively, the “FHLB-Chicago Defendants”) alleging that the FHLB-Chicago Defendants made false or misleading statements in offering materials for various RMBS sold or issued by the FHLB-Chicago Defendants or entities controlled by them. FHLB-Chicago subsequently amended the complaint to name Redwood Trust, Inc. and another one of our subsidiaries, RWT Holdings, Inc., as defendants. With respect to Redwood Trust, Inc., RWT Holdings, Inc., and SRF, the FHLB-Chicago alleges that SRF, Redwood Trust, Inc., and RWT Holdings, Inc. made false or misleading statements in the offering materials for two mortgage pass-through certificates (the “Chicago Certificates”) issued in the Sequoia Mortgage Trust 2006-1 securitization transaction (the “2006-1 RMBS”) and purchased by the FHLB-Chicago. The complaint alleges that the alleged misstatements concern, among other things, the (1) loan-to-value ratio of mortgage loans and the appraisals of the properties that secured loans supporting the 2006-1 RMBS, (2) occupancy status of the properties, (3) standards used to underwrite the loans, (4) ratings assigned to the Chicago Certificates, and (5) due diligence performed on these mortgage loans. The FHLB-Chicago alleges claims under Illinois Securities Law (815 ILCS Sections 5/12(F)-(H)) and North Carolina Securities Law (N.C.G.S.A. §78A-8(2) & §78A-56(a)) as well as a claim for negligent misrepresentation under Illinois common law. On some of the causes of action, the FHLB-Chicago seeks to rescind the purchase of the Chicago Certificates and to collect interest on the original purchase prices at the statutory interest rate of 10% per annum from the dates of original purchase (net of interest received). On one cause of action, the FHLB-Chicago seeks unspecified damages. The FHLB-Chicago also seeks attorneys’ fees and costs. The first of the Chicago Certificates was issued with an original principal amount of approximately $105 million and, as of December 31, 2013, the FHLB Chicago has received approximately $72.3 million of principal and $24.2 million of interest payments in respect of this Chicago Certificate. As of December 31, 2013, this Chicago Certificate had a remaining outstanding principal amount of approximately $32.0 million (after taking into account approximately $1.0 million of principal losses allocated to this Chicago Certificate). The second of the Chicago Certificates was issued with an original principal amount of approximately $379 million and, as of December 31, 2013, the FHLB Chicago has received approximately $258.6 million of principal and $81.5 million of interest payments in respect of this Chicago Certificate. As of December 31, 2013, this Chicago Certificate had a remaining outstanding principal amount of approximately $113.7 million (after taking into account approximately $6.3 million of principal losses allocated to this Chicago Certificate). SRF, Redwood Trust, Inc., and RWT Holdings, Inc. have denied FHLB-Chicago’s allegations. This case is in early stages of discovery, and no trial date has been set. We intend to defend the action vigorously. Redwood agreed to indemnify the underwriters of the 2006-1 RMBS, which underwriters are also named defendants in this action, for certain losses and expenses they might incur as a result of claims made against them relating to this RMBS, including, without limitation, certain legal expenses. Regardless of the outcome of this litigation, Redwood could incur a loss as a result of these indemnities.

The business of the sponsor, the depositor, the seller and their affiliates has included, and continues to include, activities relating to the acquisition and securitization of residential mortgage loans. In addition, the business of the sponsor has, in the past, included activities relating to the acquisition and securitization of debt obligations and other assets through the issuance of collateralized debt obligations (commonly referred to as CDO transactions). Because of their involvement in the securitization and CDO businesses, the sponsor, the depositor, the seller and their affiliates could become the subject of litigation relating to these businesses, including additional litigation of the type described above, and could also become the subject of governmental investigations, enforcement actions, or lawsuits and governmental authorities could allege that these entities violated applicable law or regulation in the conduct of their business.

In fact, the sponsor and its affiliates have received, and responded to, information requests and subpoenas from two governmental authorities (one by the SEC relating to the sponsor’s CDO business and one by the National Credit Union Administration relating to a residential mortgage securitization conducted by the sponsor and the depositor). It is possible that the sponsor, the depositor, the seller or their affiliates might not be successful in defending or responding to any litigation, governmental investigation or related action and any losses incurred as a result of the resolution of any such action or investigation could have a material adverse effect on the sponsor, the depositor, the seller or their affiliates. In any case, regardless of the merits of any allegation or legal action that may be brought against the sponsor, the depositor, the seller or their affiliates, or of their success in defending against such allegations or legal actions, the costs of defending against any such allegation or legal action may be significant or material and could have a material adverse effect on the sponsor, the depositor, the seller or their affiliates.

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

The seller and servicing administrator, the sponsor and the depositor are each either directly or indirectly wholly-owned subsidiaries of Redwood Trust, Inc. There is not currently, and there was not during the past two years, any material business relationship, agreement, arrangement, transaction or understanding that is or was entered into outside the ordinary course of business or is or was on terms other than would be obtained in an arm’s length transaction with an unrelated third party, between (a) any of the seller, the sponsor, the depositor and the issuing entity on the one hand and (b) any of the trustee, any servicer, the custodian, the master servicer or either originator of the mortgage loans on the other hand.

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

The reports on assessment of compliance with the servicing criteria for asset-backed securities and the related attestation reports on such assessments of compliance are attached hereto under Item 15.

The registrant has prepared the Table below in connection with this transaction. The Table shows, in one compiled format, which entity participating in a servicing function for this transaction was assigned responsibility for each criterion in Item 1122(d). In the Table below, certain criteria are not applicable, given the structure of the offering, and accordingly no entity is assigned responsibility for such criteria.

Also, Wilmington Trust, National Association (“Wilmington”), the trustee, does not participate in any servicing function for the transaction that is the subject of this 10-K filing. Therefore, there is no reference to Wilmington in the chart below; nor does this 10-K filing include any assessment or auditor report from Wilmington. Finally, any discrepancies between the chart below and the assessment of compliance exhibit provided by any party listed in the chart is explained by the fact that the chart is specific to the transaction that is the subject of this 10-K filing, whereas each party’s respective assessment of compliance is issued on a platform basis and includes coverage of other additional transactions that are not the subject of this 10-K filing.

SEQUOIA RESIDENTIAL FUNDING, INC.

SEMT 2013-8

Reg AB 1122(d)

CitiMortgage, Inc.

The assessment of compliance with applicable servicing criteria for the twelve months ended December 31, 2013, furnished pursuant to Item 1122 of Regulation AB by CitiMortgage, Inc. (the “2013 CitiMortgage Assessment”) for its platform, discloses that material instances of noncompliance occurred with respect to the servicing criteria described in Item 1122(d)(4)(vii) of Regulation AB. The 2013 CitiMortgage Assessment is attached to this Form 10-K as exhibit 33.1.

1122(d)(4)(vii)—In certain instances, the Servicer did not initiate, conduct, and conclude loss mitigation or recovery actions (e.g., forbearance plans, modifications, and deeds in lieu of foreclosure, foreclosures, and repossessions, as applicable) in accordance with the timeframes or other requirements established by the transaction agreements.

The Servicer’s internal reviews identified noncompliance related to adherence to U.S. Federal Bankruptcy Code timeliness, including proof of claim filings; late removal of accounts from bankruptcy status; bankruptcy processing controls; and bankruptcy technology risk assessment. As of September 30, 2013, sustainable corrective action plans were fully implemented to remediate this issue.

Item 1123 of Regulation AB, Servicer Compliance Statement.

The servicer compliance statements are attached hereto under Item 15.

PART IV

Item 15. Exhibits, Financial Statement Schedules.

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.

Date: March 28, 2014

EXHIBIT INDEX