csan-20251231.htm

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 20-F/A

(Amendment No. 1)

☐ REGISTRATION STATEMENT PURSUANT TO SECTION 12(b) OR (g) OF THE SECURITIES EXCHANGE ACT OF 1934

☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the fiscal year ended December 31, 2025

☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

☐ SHELL COMPANY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

Commission file number: 001-40155

COSAN S.A.
(Exact name of Registrant as specified in its charter)

COSAN INC.
(Translation of Registrant’s name into English)

Federal Republic of Brazil
(Jurisdiction of incorporation or organization)

Av. Brigadeiro Faria Lima, 4,100 – 16th floor
São Paulo – SP, 04538-132, Brazil
+55 11 3897-9797
(Address of principal executive offices)

José Cezário Menezes de Barros Sobrinho

+55 11 3897-9797

ri@cosan.com

Av. Brigadeiro Faria Lima, 4,100 – 16th floor

São Paulo – SP, 04538-132, Brazil

(Name, Telephone, Email 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	Trading Symbol	Name of Each Exchange on Which Registered
American depositary shares, each representing four common shares, no par value	—	N/A
Common shares, no par value*		N/A

Securities registered or to be registered pursuant to Section 12(g) of the Act.

None

Securities for which there is a reporting obligation pursuant to Section 15(d) of the Act.

None

Indicate the number of outstanding shares of each of the issuer’s classes of capital or common stock as of the close of the period covered by the annual report.

The number of outstanding shares as of December 31, 2025 was:

Title of Class	Number of Shares Outstanding
Common shares, no par value	3,966,570,932

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 ☒

Note – Checking the box above will not relieve any registrant required to file reports pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 from their obligations under those Sections.

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, or an emerging growth company. See definition of “large accelerated filer,” “accelerated filer,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

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. ☒

Auditor Name: PricewaterhouseCoopers Auditores Independentes Ltda. Auditor Location: São Paulo, Brazil Auditor Firm ID: 1351

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 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 ☒

EXPLANATORY NOTE

We are amending our Annual Report on Form 20-F for the fiscal year ended December 31, 2025 as originally filed with the U.S. Securities and Exchange Commission (the “SEC”) on April 10, 2026 (the “Original Annual Report”) for the purpose of filing with the SEC the financial statements for the fiscal years ended March 31, 2026, 2025 and 2024 of Raízen S.A. as Exhibit 15.2.

Other than set forth above, this Form 20-F/A does not, and does not purport to, amend, update or restate the information in any other item of the Original Annual Report as originally filed with the SEC. As a result, this Form 20-F/A does not reflect any events that may have occurred after the Original Annual Report was filed on April 10, 2026.

PART III

Item 17. Financial Statements

We have responded to Item 18 in lieu of responding to this Item.

Item 18. Financial Statements

See our audited consolidated financial statements beginning on page F-1 of this Amendment No. 1 to the Original Annual Report.

Item 19. Exhibits

We are filing the following documents as part of this annual report on Form 20-F:

Exhibit Number	Exhibit
1.1	By-Laws of Cosan S.A. (incorporated by reference to Exhibit 1.1 of Cosan S.A.’s annual report on Form 20-F for the year ended December 31, 2025).
2.1	Indenture dated November 5, 2010 among Cosan Overseas Limited, Cosan S.A. Indústria e Comércio, The Bank of New York Mellon, as Trustee, New York Paying Agent, Transfer Agent and Registrar, The Bank of New York Mellon (London Branch), as London Paying Agent and The Bank of New York Mellon (Luxembourg) S.A., as Paying Agent and Transfer Agent (incorporated by reference to Exhibit 2.5 of Cosan Limited’s annual report on Form 20‑F for the year ended March 31, 2011).
2.2	Description of Securities (incorporated by reference to Exhibit 2.2 of Cosan S.A.’s annual report on Form 20-F for the year ended December 31, 2025).
2.3	Form of Deposit Agreement among Cosan S.A., J.P. Morgan Chase Bank N.A., as depositary, and the holders from time to time of American depositary shares issued thereunder, including the form of American depositary receipts (incorporated by reference to Exhibit 99(a) to the Registration Statement on Form F‑6 (file no. 333-253471) filed with the SEC on February 24, 2021).
2.4	Amendment No. 1 to the Deposit Agreement among Cosan S.A., J.P. Morgan Chase Bank N.A., as depositary, and the holders from time to time of American depositary shares issued thereunder, including the form of American depositary receipts (incorporated by reference to Exhibit 99(a)(2) to the Registration Statement on Form F-6 POS (file no. 333-253471) filed with the SEC on May 7, 2021).

Exhibit Number	Exhibit
4.1	Framework Agreement dated August 25, 2010 among Cosan S.A. Indústria e Comércio, Cosan Distribuidora de Combustíveis S.A., Cosan Limited, Houches Holdings S.A., Shell Brasil Limitada, Shell Brazil Holding B.V., Shell Overseas Holdings Limited and Milimétrica Participações S.A., or Framework Agreement (incorporated by reference to Exhibit 4.3 of Cosan Limited’s annual report on Form 20‑F for the year ended March 31, 2010).
4.2	First Amendment to the Framework Agreement dated as of April 7, 2011 (incorporated by reference to Exhibit 4.4 of Cosan Limited’s annual report on Form 20‑F for the year ended March 31, 2011).
4.3	Second Amendment to the Framework Agreement dated as of June 1, 2011 (incorporated by reference to Exhibit 4.5 of Cosan Limited’s annual report on Form 20‑F for the year ended March 31, 2011).
4.4	Third Amendment to the Framework Agreement dated as of March 21, 2012 (incorporated by reference to Exhibit 4.5 of Cosan Limited’s annual report on Form 20‑F for the year ended December 31, 2017).
4.5	Amendment and Restatement Deed to the Joint Venture Agreement among Cosan S.A., Cosan Investimentos e Participações S.A., Raízen S.A., Shell Brazil Holding B.V. and Shell Overseas Holdings Limited dated as of July 11, 2021 (incorporated by reference to Exhibit 4.6 of Cosan S.A.’s annual report on Form 20-F for the year ended December 31, 2021).
4.6	Operating and Coordination Agreement dated June 1, 2011 relating to Raízen Energia Participações S.A., Raízen Combustíveis S.A. and Raízen S.A. (incorporated by reference to Exhibit 4.7 of Cosan Limited’s annual report on Form 20‑F for the year ended March 31, 2011).
4.7	Eight Amendment to the Shareholders’ Agreement of Raízen S.A. dated as of July 27, 2023 (incorporated by reference to Exhibit 4.7 of Cosan S.A.’s annual report on Form 20-F for the year ended December 31, 2023).
4.8	Share Purchase Agreement for the acquisition of Comma Oil & Chemicals Limited dated February 29, 2012, between Esso Petroleum Company, Limited and Cosan S.A. Indústria e Comércio (incorporated by reference to Exhibit 4.11 of Cosan Limited’s annual report on Form 20‑F for the year ended March 31, 2013).
4.9	Share Purchase Agreement for the acquisition of Comgás dated May 28, 2012, between Integra Investments B.V., BG Energy Holdings Limited, Provence Participações S.A. and Cosan S.A. Indústria e Comércio (incorporated by reference to Exhibit 4.12 of Cosan Limited’s annual report on Form 20‑F for the year ended March 31, 2013).
4.10	Deed of Merger Cosan Limited and Cosan S.A. (incorporated by reference to Exhibit 4.13 of Cosan S.A.’s annual report on Form 20‑F for the year ended December 31, 2020).
4.11	English translation of the Merger and Justification Protocol between Cosan Limited and Cosan S.A. (incorporated by reference to Exhibit 4.14 of Cosan S.A.’s annual report on Form 20‑F for the year ended December 31, 2020).
4.12	English translation of the Merger and Justification Protocol between Cosan Logística and Cosan S.A. (incorporated by reference to Exhibit 4.15 of Cosan S.A.’s annual report on Form 20‑F for the year ended December 31, 2020).
4.13	English translation of the Protocol and Justification of Merger of Cosan Investimentos e Participações S.A. into Cosan S.A. dated as of October 27, 2021 (incorporated by reference to Exhibit 4.16 of Cosan S.A.’s annual report on Form 20-F for the year ended December 31, 2021).
4.14	English translation of the Master Derivatives Agreement dated October 5, 2022, between Cosan Oito S.A. and Banco J.P. Morgan S.A. (incorporated by reference to Exhibit 4.15 of Cosan S.A.’s annual report on Form 20-F for the year ended December 31, 2022).
4.15	Schedule dated October 5, 2022, to the Master Derivatives Agreement dated as of October 5, 2022, between Cosan Oito S.A. and Banco J.P. Morgan S.A. (incorporated by reference to Exhibit 4.16 of Cosan S.A.’s annual report on Form 20-F for the year ended December 31, 2022).
4.16	English translation of the Master Derivatives Agreement dated October 5, 2022, between Cosan Oito S.A. and Banco Citibank S.A. (incorporated by reference to Exhibit 4.17 of Cosan S.A.’s annual report on Form 20-F for the year ended December 31, 2022).
4.17	Schedule dated October 5, 2022, to the Master Derivatives Agreement dated as of October 5, 2022, between Cosan Oito S.A. and Banco Citibank S.A. (incorporated by reference to Exhibit 4.18 of Cosan S.A.’s annual report on Form 20-F for the year ended December 31, 2022).
4.18	Loan Agreement dated October 7, 2022, among Cosan Oito S.A., JP Morgan Chase Bank N.A., London Branch and Banco J.P. Morgan S.A. (incorporated by reference to Exhibit 4.19 of Cosan S.A.’s annual report on Form 20-F for the year ended December 31, 2022).

Exhibit Number	Exhibit
4.19	Loan Agreement dated October 7, 2022, among Cosan Oito S.A., Citibank, N.A., London Branch, and Citigroup Global Markets Brasil, Corretora de Câmbio, Títulos e Valores Mobiliários S.A. (incorporated by reference to Exhibit 4.20 of Cosan S.A.’s annual report on Form 20-F for the year ended December 31, 2022).
4.20	Confirmation of Derivative Transaction – Collar Plus Forward dated October 7, 2022, among Cosan Oito S.A. and Banco J.P. Morgan S.A. (incorporated by reference to Exhibit 4.23 of Cosan S.A.’s annual report on Form 20-F for the year ended December 31, 2022).*
4.21	Confirmation of Derivative Transaction – Collar Plus Forward dated October 7, 2022, among Cosan Oito S.A. and Banco Citibank S.A. (incorporated by reference to Exhibit 4.24 of Cosan S.A.’s annual report on Form 20-F for the year ended December 31, 2022).*
4.22	English translation of the Investment Agreement dated as of September 21, 2025 between Aguassanta Investimentos S.A., Queluz Holding Limited, certain Class A funds of Perfin Rally Fundo de Investimento em Participações Multiestratégia Responsabilidade Limitada, Classe Única BTG Pactual Infraestrutura III Fundo de Investimento em Participações Multiestratégia, Classe Única Fundo de Investimento em Participações BPAC3 – Multiestratégia Responsabilidade Limitada and Cosan S.A. and Aguassanta Um Participações S.A. as intervening-consenting parties (incorporated by reference to Exhibit 4.22 of Cosan S.A.’s annual report on Form 20-F for the year ended December 31, 2025).
4.23	English translation of the Shareholders’ Agreement dated as of November 7, 2025 between Aguassanta Investimentos S.A., Queluz Holding Limited, Classe do Perfin Rally Fundo de Investimento em Participações Multiestratégia Responsabilidade Limitada, Classe Única BTG Pactual Infraestrutura III Fundo de Investimento em Participações Multiestratégia, Classe Única Fundo de Investimento em Participações BPAC3 – Multiestratégia Responsabilidade Limitada, BTG Pactual Co-Investimento Cosan Fundo de Investimento em Participações Multiestratégia Responsabilidade Limitada, and Vertiz Holding S.A., Cosan S.A. and Rubens Ometto Silveira Mello as intervening-consenting parties (incorporated by reference to Exhibit 4.23 of Cosan S.A.’s annual report on Form 20-F for the year ended December 31, 2025).
8.1	Subsidiaries of the Registrant (incorporated by reference to Exhibit 8.1 of Cosan S.A.’s annual report on Form 20-F for the year ended December 31, 2025).
11.1	Code of Ethics (incorporated by reference to Exhibit 11.1 of Cosan S.A.’s annual report on Form 20-F for the year ended December 31, 2023).
11.2	Insider Trading Policy (incorporated by reference to Exhibit 11.2 of Cosan S.A.’s annual report on Form 20-F for the year ended December 31, 2025).
12.1**	Certification pursuant to section 302 of the Sarbanes‑Oxley Act of 2002 of the Chief Executive Officer.
12.2**	Certification pursuant to section 302 of the Sarbanes-Oxley Act of 2002 of the Chief Financial Officer.
13.1**	Certification pursuant to 18 U.S.C. section 1350, as adopted pursuant to section 906 of the Sarbanes-Oxley Act of 2002, of the Chief Executive Officer.
13.2**	Certification pursuant to 18 U.S.C. section 1350, as adopted pursuant to section 906 of the Sarbanes-Oxley Act of 2002, of the Chief Financial Officer.
15.1***	Financial statements of Vale S.A. as of December 31, 2025 and 2024 and for the years ended December 31, 2025, 2024 and 2023, the Report of Vale S.A. Independent Registered Public Accounting Firm and Vale S.A. Management’s Report on Internal Control over Financial Reporting (incorporated by reference to pages F-1 to F-104 of the annual report of Vale S.A. on Form 20-F for the year ended December 31, 2025 filed with the SEC on March 27, 2026 (File No. 001-15030)).**
15.2**	Financial Statements for the fiscal years ended March 31, 2026, 2025 and 2024 of Raízen S.A.
97.1	Clawback Policy (incorporated by reference to Exhibit 97.1 of Cosan S.A.’s annual report on Form 20-F for the year ended December 31, 2023).
101.INS	XBRL Instance Document
101.SCH	XBRL Taxonomy Extension Schema Document
101.CAL	XBRL Taxonomy Extension Calculation Linkbase Document
101.DEF	XBRL Taxonomy Extension Definition Linkbase Document
101.LAB	XBRL Taxonomy Extension Label Linkbase Document
101.PRE	XBRL Taxonomy Extension Presentation Linkbase Document


*	Portions of this item have been omitted pursuant to a request for confidential treatment.
**	Filed herewith.
***	We are incorporating by references Vale S.A.’s audited consolidated financial statements as of December 31, 2025 and 2024 and for the years ended December 31, 2025, 2024 and 2023. As the Company substantially disposed of its investment in Vale S.A. during 2025, the impact of the equity method of accounting on Cosan’s consolidated financial statements for the year ended December 31, 2025 is not material.

SIGNATURES

The registrant hereby certifies that it meets all of the requirements for filing on Form 20-F and that it has duly caused and authorized the undersigned to sign this Amendment No. 1 to the annual report on its behalf.

COSAN S.A.
By:	/s/ José Cezário Menezes de Barros Sobrinho
	Name:	José Cezário Menezes de Barros Sobrinho
	Title:	Chief Financial and Investor Relations Officer

Date: October 14, 2026