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
.   SANTANDER
DRIVE AUTO RECEIVABLES TRUST 2021-1 (Exact name of issuing entity as specified in its
charter) Commission file number of the issuing entity:
333-228364-13 Central Index Key Number of issuing
entity: 0001839893 SANTANDER DRIVE AUTO RECEIVABLES LLC (Exact name of depositor as specified in its charter) Commission file number of depositor: 333-228364 Central Index Key Number of depositor: 0001383094 SANTANDER CONSUMER USA INC. (Exact name of sponsor as specified in its charter)   Central Index
Key Number of sponsor: 0001540151 Delaware (State or other jurisdiction of incorporation or organization of the issuing entity) 86-6367386 (I.R.S. Employer Identification No. of the issuing entity) c/o Santander Drive Auto Receivables LLC 1601 Elm Street, Suite 800 Dallas, Texas 75201 (Address of principal executive offices) (214) 292-1930 (Telephone number, including area code) Securities Registered Pursuant to Section 12(b) of the Securities Exchange Act of 1934: None Securities Registered Pursuant to Section 12 (g) of the Securities Exchange Act of 1934: None Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities
Act. Yes ☐   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 ☐   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. Yes ☒   No ☐ Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted 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 such files). Yes ☒   No ☐ Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated
filer, a smaller reporting company, or an emerging growth company. See the definitions of large accelerated filer, accelerated filer, smaller reporting company, and emerging growth company in Rule 12b-2 of the Exchange Act.  Large accelerated filer

☐

Accelerated filer

☐Non-accelerated filer

☒

Smaller reporting company

☐Emerging growth company

☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period
for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐ Indicate
by check mark whether the registrant has filed a report on and attestation to its managements assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the
Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report. ☐ If securities are registered pursuant to Section 12(b) of the Act, indicate by check mark whether the financial statements of the registrant included in
the filing reflect the correction of an error to previously issued financial statements. ☐ Indicate by check mark whether any of those error
corrections are restatements that required a recovery analysis of incentive-based compensation received by any of the registrants executive officers during the relevant recovery period pursuant to §240.10D-1(b). ☐ Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act). Yes ☐  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 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 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). None




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PART I The following items have been omitted in accordance with General Instruction J to Form 10-K:  Item 1

BusinessItem 1A

Risk FactorsItem 1C

CybersecurityItem 2

PropertiesItem 3

Legal Proceedings  Item 1B.
Unresolved Staff Comments Nothing to report.  Item 4.
Mine Safety Disclosures Not applicable. Substitute information provided in
accordance with General Instruction J to Form 10-K: Item 1112(b) of Regulation AB. Significant
Obligors of Pool Assets (Financial Information) Nothing to report. Item 1114(b)(2) of Regulation AB. Credit Enhancement and Other Support, Except for Certain Derivatives Instruments (Information Regarding Significant
Enhancement Providers) Nothing to report. Item 1115(b) of Regulation AB. Certain Derivatives Instruments (Financial Information) Nothing to report. Item 1117 of Regulation AB. Legal
Proceedings. Wells Fargo Bank, N.A. (Wells Fargo Bank), as indenture trustee, has provided the following information: In December 2014, Phoenix Light SF Limited (Phoenix Light) and certain related entities filed a complaint in the United States District Court for the Southern
District of New York alleging claims against Wells Fargo Bank, N.A., in its capacity as trustee for a number of residential mortgage-backed securities (RMBS) trusts. Complaints raising similar allegations have been filed by Commerzbank AG in the
Southern District of New York, IKB International and IKB Deutsche Industriebank (together, IKB) in New York state court, and Park Royal I LLC and Park Royal II LLC in New York state court. In each case, the plaintiffs allege that Wells Fargo
Bank, N.A., as trustee, caused losses to investors, and plaintiffs assert causes of action based upon, among other things, the trustees alleged failure to notify and enforce repurchase obligations of mortgage loan sellers for purported
breaches of representations and warranties, notify investors of alleged events of default, and abide by appropriate standards of care following alleged events of default. In July 2022, the district court dismissed Phoenix Lights claims
and certain of the claims asserted by Commerzbank AG, and subsequently entered judgment in each case in favor of Wells Fargo Bank, N.A. In August 2022, Phoenix Light and Commerzbank AG each appealed the district courts decision to the United
States Court of Appeals for the Second Circuit. Phoenix Light dismissed its appeal in May 2023, terminating its case. In November 2023, Wells Fargo Bank, N.A. entered into an agreement with IKB to resolve IKBs claims. Wells Fargo Bank, N.A.
previously settled two class actions filed by institutional investors and an action filed by the National Credit Union Administration with similar allegations.  2




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PART II The following items have been omitted in accordance with General Instruction J to Form 10-K:  Item 5

Market for Registrants Common Equity, Related Stockholder Matters and Issuer Purchases of Equity SecuritiesItem 6

[Reserved]Item 7

Managements Discussion and Analysis of Financial Condition and Results of OperationsItem 7A

Quantitative and Qualitative Disclosures about Market RiskItem 8

Financial Statements and Supplementary DataItem 9

Changes in and Disagreements With Accountants on Accounting and Financial DisclosureItem 9A

Controls and Procedures  Item 9B.
Other Information None.  Item 9C.
Disclosure Regarding Foreign Jurisdictions that Prevent Inspections Not applicable.  3




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PART III The following items have been omitted in accordance with General Instruction J to Form 10-K:  Item 10

Directors, Executive Officers, and Corporate GovernanceItem 11

Executive CompensationItem 12

Security Ownership of Certain Beneficial Owners and Management and Related Stockholder MattersItem 13

Certain Relationships and Related Transactions, and Director IndependenceItem 14

Principal Accountant Fees and Services Substitute information provided in accordance with General Instruction J to Form
10-K: Item 1119 of Regulation AB. Affiliations and Certain Relationships and Related Transactions Information required by Item 1119 of Regulation AB has been omitted from this report on Form 10-K in reliance
on the Instruction to Item 1119. Item 1122 of Regulation AB. Compliance with Applicable Servicing Criteria Each of Santander Consumer USA Inc., Wells Fargo Bank, N.A. and Computershare Trust Company, N.A. (each, a Servicing Participant) have been
identified by the issuing entity as parties participating in the servicing function with respect to the pool assets held by the issuing entity. Each of the Servicing Participants has completed a report on an assessment of compliance with the
servicing criteria applicable to it (each, a Report on Assessment), which Reports on Assessment are attached as exhibits to this Form 10-K. In addition, each of the Servicing Participants has
provided an attestation report (each, an Attestation Report) by one or more registered public accounting firms, which reports are also attached as exhibits to this Form 10-K. None of the Reports on Assessment or the related Attestation Reports has identified any material instances of noncompliance with the servicing criteria
described in the related Report on Assessment as being applicable to such Servicing Participant. Item 1123 of Regulation AB. Servicer Compliance
Statements Santander Consumer USA Inc. has been identified by the issuing entity as the servicer with respect to the asset pool held by the issuing
entity. Santander Consumer USA Inc. has completed a statement of compliance with applicable servicing criteria (a Compliance Statement) signed by an authorized officer. The Compliance Statement is attached as an exhibit to this Form 10-K.  4




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PART IV  Item 15.
Exhibit and Financial Statement Schedules  (a)(1)

Not Applicable.(a)(2)

Not Applicable.(a)(3)

See Item 15(b) below. (b) Exhibits The exhibits
listed below are either included or incorporated by reference as indicated:  Exhibit No.

Description1.1

Underwriting Agreement, dated as of February 
9, 2021, among Santander Drive Auto Receivables LLC (Santander Drive), Santander Consumer USA Inc. (SC) and J.P. Morgan Securities LLC, as representative of the several underwriters (incorporated by reference to Exhibit 1.1 of Form
8-K filed by the Issuer (Commission File No. 333-228364-13) with the Securities and Exchange Commission on February 11,
2021)3.1

Amended and Restated Limited Liability Company Agreement of Santander Drive dated as of March 
7, 2007 (incorporated by reference to Exhibit 3.1 of Form SF-3 filed by Santander Drive (Commission File No. 
333-228364) with the Securities and Exchange Commission on November 13, 2018)3.2

First Amendment to Amended and Restated Limited Liability Company Agreement, dated as of February 
28, 2017, by SC, as sole equity member (incorporated by reference to Exhibit 3.2 of Form SF-3 filed by Santander Drive (Commission File No. 
333-228364) with the Securities and Exchange Commission on November 13, 2018)4.1

Indenture, dated as of February 
17, 2021, between Santander Drive Auto Receivables Trust 2021-1, as issuer (the Issuer), and Wells Fargo Bank, National Association, as indenture trustee (the Indenture Trustee) (incorporated
 by reference to Exhibit 4.1 of Form 8-K filed by the Issuer (Commission File No. 333-228364-13) with the Securities and
Exchange Commission on February 18, 2021)10.1

Purchase Agreement, dated as of February 17, 2021, between SC and Santander Drive (incorporated by reference to Exhibit 10.1 of Form 8-K filed by the Issuer (Commission File No. 333-228364-13) with the Securities and Exchange Commission on February 
18, 2021)10.2

Sale and Servicing Agreement, dated as of February 
17, 2021, among the Issuer, Santander Drive, SC and the Indenture Trustee (incorporated by reference to Exhibit 10.2 of Form 8-K filed by the Issuer (Commission File No. 333-228364-13) with the Securities and Exchange Commission on February 18, 2021)10.3

Administration Agreement, dated as of February 
17, 2021, among the Issuer, SC, as administrator, and the Indenture Trustee (incorporated by reference to Exhibit 10.3 of Form 8-K filed by the Issuer (Commission File No. 333-228364-13) with the Securities and Exchange Commission February 18, 2021)10.4

Amended and Restated Trust Agreement, dated as of February 
17, 2021, between Santander Drive and Wilmington Trust, National Association, not in its individual capacity but solely as owner trustee for the Issuer (incorporated by reference to Exhibit 10.4 of Form 8-K filed
 by the Issuer (Commission File No. 333-228364-13) with the Securities and Exchange Commission on February 18, 2021)  5




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10.5

Asset Representations Review Agreement, dated as of February 
17, 2021, among the Issuer, SC, as sponsor and servicer, and Clayton Fixed Income Services, LLC, as asset representations reviewer (incorporated by reference to Exhibit 10.5 of Form 8-K filed by the Issuer (Commission
 File No. 333-228364-13) with the Securities and Exchange Commission on February 18, 2021)10.6

First Amendment to Sale and Servicing Agreement, dated as of August 
16, 2021, by and among Santander Drive, as seller, and SC, as servicer (incorporated by reference to Exhibit 10.2 of Form 10-D/A filed by the Issuer (Commission File No. 333-228364-13) with the Securities and Exchange Commission on August 18, 2021)10.7

Second Amended and Restated Servicing Agreement, dated as of October 
31, 2021, among Wells Fargo Bank, N.A., Wells Fargo Delaware Trust Company, N.A., Computershare Trust Company, N.A. and Computershare Limited (incorporated by reference to Exhibit 99.1 of Form 8-K filed by the Issuer
 (Commission File No. 333-228364-13) with the Securities and Exchange Commission on November 5, 2021)31.1

Certification (Santander Drive)33.1

Managements Assessment of Compliance with SEC Regulation AB Servicing Criteria (SC)33.2

Assessment of Compliance with the Applicable Servicing Criteria (Wells Fargo Bank, N.A.)33.3

Assessment of Compliance with the Applicable Servicing Criteria (Computershare Trust Company, N.A.)34.1

Report of Independent Registered Public Accounting Firm (PricewaterhouseCoopers LLP with respect to SC)34.2

Report of Independent Registered Public Accounting Firm (KPMG LLP with respect to Wells Fargo Bank, N.A.)34.3

Report of Independent Registered Public Accounting Firm (PricewaterhouseCoopers LLP with respect to Computershare Trust Company, N.A.)35.1

Servicer Compliance Statement (SC)  (c)
Not Applicable.  Item 16.
Form 10-K Summary None. Supplemental information to be Furnished With Reports
Filed Pursuant to Section 15(d) of the Act by Registrants Which Have Not Registered Securities Pursuant to Section 12 of the Act No annual
report, proxy statement, form of proxy or other proxy soliciting material has been sent to certificateholders, and the registrant does not presently contemplate sending any such materials subsequent to the filing of this report.  6




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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. Date: March 29, 2024  SANTANDER DRIVE AUTO RECEIVABLES LLC, as depositorBy:

/s/ Corey HenryName:

Corey HenryTitle:

President and Chief Executive Officer (senior
officer in charge of securitization of the depositor)
  7