SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 20-F (Mark One) ☐REGISTRATION STATEMENT PURSUANT TO SECTION 12(b) OR (g) OF THE SECURITIES EXCHANGE ACT OF 1934 OR ☒ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ending December 31, 2020 OR ☐TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to ☐ SHELL COMPANY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of event requiring this shell company report Commission file number 001-12518 BANCO SANTANDER, S.A. (Exact name of Registrant as specified in its charter) Kingdom of Spain (Jurisdiction of incorporation) Ciudad Grupo Santander 28660 Boadilla del Monte (Madrid), Spain (address of principal executive offices) José G. Cantera Banco Santander, S.A. Ciudad Grupo Santander - 28660 Boadilla del Monte Madrid, Spain Tel: +34 91 289 32 80 Fax: +34 91 257 12 82 (Name, Telephone, E-mail and/or Facsimile number and Address of Company Contact Person) Securities registered or to be registered, pursuant to Section 12(b) of the Act Title of each class Name of each exchange on which registered American Depositary Shares, each representing the right to receive one Share of Capital Stock of Banco Santander, S.A., par value euro 0.50 each SAN New York Stock Exchange Shares of Capital Stock of Banco Santander, S.A., par value euro 0.50 each Not applicable New York Stock Exchange * Non-cumulative Preferred Stock Series 6 SAN PRB New York Stock Exchange Senior Non Preferred Floating Rate Notes due 2023 SAN 23A New York Stock Exchange 3.500% Second Ranking Senior Debt Securities due 2022 SAN 22 New York Stock Exchange 4.250% Second Ranking Senior Debt Securities due 2027 SAN27 New York Stock Exchange Second Ranking Senior Floating Rate Notes due 2022 SAN22A New York Stock Exchange 3.125% Senior Non Preferred Fixed Rate Notes due 2023 SAN23 New York Stock Exchange 3.800% Senior Non Preferred Fixed Rate Notes due 2028 SAN28 New York Stock Exchange Series 76 2.706% Senior Preferred Fixed Rate Notes due 2024 SAN24 New York Stock Exchange Series 77 3.306% Senior Non Preferred Fixed Rate Notes due 2023 SAN29 New York Stock Exchange Series 37 3.848% Senior Non Preferred Fixed Rate Notes due 2023 SAN23B New York Stock Exchange Series 38 4.379% Senior Non Preferred Fixed Rate Notes due 2028 SAN28A New York Stock Exchange Series 36 Senior Non Preferred Floating Rate Notes due 2023 SAN23C New York Stock Exchange Series 26 Subordinated Debt Securities SAN /25 New York Stock Exchange Series 92 2.746% Senior Non Preferred Fixed Rate Notes due 2025 SAN25 New York Stock Exchange Series 93 3.490% Senior Non Preferred Fixed Rate Notes due 2030 SAN30 New York Stock Exchange Series 100 2.749% Tier 2 Subordinated Fixed Rate Notes due 2030 SAN30A New York Stock Exchange *Banco Santander Shares are not listed for trading, but are only listed in connection with the registration of the American Depositary Shares, pursuant to requirements of the New York Stock Exchange. Securities registered or to be registered pursuant to Section 12(g) of the Act: None (Title of Class) Securities for which there is a reporting obligation pursuant to Section 15(d) of the Act: None (Title of Class) Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes ☒ No ☐ If this report is an annual or transition report, indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934. 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 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, or a non-accelerated filer. See definition of “accelerated filer and large accelerated filer” in Rule 12b-2 of the Exchange Act. (Check one): Large accelerated filer ☒ Accelerated filer ☐ Non-accelerated filer ☐ Emerging growth company ☐ If an emerging growth company that prepares its financial statements in accordance with U.S. GAAP, 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. ☐ † The term “new or revised financial accounting standard” refers to any update issued by the Financial Accounting Standards Board to its Accounting Standards Codification after April 5, 2012. 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. Yes ☒ No ☐ Indicate by check mark which basis of accounting the registrant has used to prepare the financial statements included in this filing: U.S. GAAP ☐ International Financial Reporting Standards as issued by the International Accounting Standards Board ☒ Other ☐ If “Other” has been checked in response to the previous question indicate by check mark which financial statement item the registrant has elected to follow. Item 17 ☐ Item 18 ☐ If this is an annual report, indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes ☐No ☒ Indicate the number of outstanding shares of each of the issuer’s classes of capital stock or common stock as of the close of business covered by the annual report 17,340,641,302 shares BANCO SANTANDER, S.A. This annual report on Form 20-F for the year ended 31 December 2020, includes three parts: (i) consolidated directors’ report, (ii) consolidated financial statements, and (iii) supplemental information. Set forth below is a table listing the required items for Form 20-F and the location where the relevant disclosure in this annual report can be found. CROSS REFERENCE TO FORM 20-F Form 20-F Item Number and Caption Location Page Presentation of Financial and Other Information Supplemental information. Section 1 859 Cautionary Statement Regarding Forward-Looking Statements Supplemental information. Section 2 860 PART I ITEM 1. IDENTITY OF DIRECTORS, SENIOR MANAGEMENT AND ADVISERS A. Directors and Senior Management Not required for Annual Report on Form 20-F - B. Advisers Not required for Annual Report on Form 20-F - C. Auditors Not required for Annual Report on Form 20-F - ITEM 2. OFFER STATISTICS AND EXPECTED TIMETABLE A. Offer Statistics Not required for Annual Report on Form 20-F - B. Method and Expected Timetable Not required for Annual Report on Form 20-F - ITEM 3. KEY INFORMATION A. Selected financial data Supplemental information. Section 3 862 B. Capitalization and indebtedness Not required for Annual Report on Form 20-F - C. Reasons for the offer and use of proceeds Not required for Annual Report on Form 20-F - D. Risk factors Supplemental information. Section 4 865 ITEM 4. INFORMATION ON THE COMPANY A. History and development of the company General Information 854 Acquisitions, Dispositions, Reorganizations Note 3. b) to our consolidated financial statements 591 Capital Increases Note 31 to our consolidated financial statements 672 Recent Events Note 1. g) to our consolidated financial statements 543 Supplemental information. Section13 955 B. Business overview Directors' Report. Economic and Financial Review 318 Selected Statistical information Supplemental information. Section 5 898 Note 6 to our consolidated financial statements 612 Note 10 to our consolidated financial statements 616 Note 20 to our consolidated financial statements 636 Note 21 to our consolidated financial statements 636 Competition in Spain Supplemental information. Section 9 922 Supervision and Regulation Supplemental information. Section 10 923 Note 1.e) to our consolidated financial statements 543 C. Organizational structure Appendix I, II and III to our consolidated financial statements 810 Note 1.a) to our consolidated financial statements 543 Cross-reference to Form 20-F Part 1. Consolidated directors' report Part 2. Consolidated financial statements Part 3. Supplemental information Form 20-F Item Number and Caption Location Page D. Property, plant and equipment Note 16 to our consolidated financial statements 628 Directors' Report. Economic and Financial Review. Section 4.3 (for number of branches in segments and units) 369 ITEM 4A. UNRESOLVED STAFF COMMENTS Supplemental information. Section 13 955 ITEM 5. OPERATING AND FINANCIAL REVIEW AND PROSPECTS Critical accounting policies Note 2 to our consolidated financial statements 550 Note 17 to our consolidated financial statements 631 Note 18 to our consolidated financial statements 634 A. Operating results Directors' Report. Economic and Financial Review. Sections 3 and 4 325 Supplemental information. Section 6 919 B. Liquidity and capital resources Directors' Report. Economic and Financial Review. Section 3.4 and 3.5 345 C. Research and development, patents and licenses, etc. Note 18 to our consolidated financial statements 634 Directors' Report. Economic and Financial Review. Section 5 409 D. Trend information Directors' Report. Economic and Financial Review. Section 7 412 E. Off-balance sheet arrangements Note 35 to our consolidated financial statements 674 F. Tabular disclosure of contractual obligations Supplemental information. Section 7 920 ITEM 6. DIRECTORS, SENIOR MANAGEMENT AND EMPLOYEES A. Directors and senior management Directors' Report. Corporate Governance. Section 4 and 5 198 B. Compensation Note 5 to our consolidated financial statements 597 Directors' Report. Corporate Governance. Section 6 249 C. Board practices Directors' Report. Corporate Governance. Section 4.2 to 4.10 206 D. Employees Supplemental information. Section 8 921 E. Share ownership Supplemental information. Section 13 955 ITEM 7. MAJOR SHAREHOLDERS AND RELATED PARTY TRANSACTIONS A. Major shareholders Directors' Report. Corporate Governance. Section 2.3 and 2.4 186 B. Related party transactions Notes 5.f) to our consolidated financial statements 597 Note 52 to our consolidated financial statements 757 Directors' Report. Corporate Governance. Section 4.12 243 C. Interests of experts and counsel Not required for Annual Report on Form 20-F - ITEM 8. FINANCIAL INFORMATION A. Consolidated statements and other financial information Financial statements Consolidated financial statements 511 Legal proceedings Note 25 to our consolidated financial statements 645 Cross-reference to Form 20-F Part 1. Consolidated directors' report Part 2. Consolidated financial statements Part 3. Supplemental information Form 20-F Item Number and Caption Location Page Shareholders remuneration Supplemental information. Section 11 944 Directors' Report. Corporate Governance. Section 3.3 193 Note 4 to our consolidated financial statements 594 B. Significant Changes Not applicable - ITEM 9. THE OFFER AND LISTING A. Offer and listing details Supplemental information. Section 12 944 B. Plan of distribution Not required for Annual Report on Form 20-F - C. Markets Supplemental information. Section 12 944 Directors' Report. Corporate Governance. Section 2.6 188 D. Selling shareholders Not required for Annual Report on Form 20-F - E. Dilution Not required for Annual Report on Form 20-F - F. Expense of the issue Not required for Annual Report on Form 20-F - ITEM 10. ADDITIONAL INFORMATION A. Share capital Not required for Annual Report on Form 20-F - B. Memorandum and articles of association Supplemental information. Section 13 947 Directors' Report. Corporate Governance. Sections 2.1 and 2.2 185 Directors' Report. Corporate Governance. Sections 3.2; 3.3; 3.4 and 3.5 192 Directors' Report. Corporate Governance. Sections 4.2 and 4.3 206 Directors' Report. Corporate Governance. Section 4.12 243 Directors' Report. Corporate Governance. Section 6 249 C. Material contracts Supplemental information. Section 13 950 D. Exchange controls Supplemental information. Section 13 950 E. Taxation Supplemental information. Section 13 951 F. Dividends and paying agents Not required for Annual Report on Form 20-F - G. Statement by experts Not required for Annual Report on Form 20-F - H. Documents on display Supplemental information. Section 13 955 I. Subsidiary information Not required for Annual Report on Form 20-F - ITEM 11. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK Directors' Report. Risk Management and compliance. Section 4 469 ITEM 12. DESCRIPTION OF SECURITIES OTHER THAN EQUITY SECURITIES A. Debt Securities Not required for Annual Report on Form 20-F - B. Warrants and Rights Not required for Annual Report on Form 20-F - C. Other Securities Not required for Annual Report on Form 20-F - D. American Depositary Shares Supplemental information. Section 12 944 PART II ITEM 13. DEFAULTS, DIVIDEND ARREARAGES AND DELINQUENCIES Not applicable - ITEM 14. MATERIAL MODIFICATIONS TO THE RIGHTS OF SECURITY HOLDERS AND USE OF PROCEEDS Not applicable - Cross-reference to Form 20-F Part 1. Consolidated directors' report Part 2. Consolidated financial statements Part 3. Supplemental information