UNITED STATES

SECURITIES AND EXCHANGECOMMISSION

Washington, D.C.20549

FORM 6-K

Report of Foreign PrivateIssuer
Pursuant to Rule 13a-16 or 15d-16 of the

Securities ExchangeAct of 1934

For the month ofOctober, 2025

Commission File Number1-15106

PETRÓLEO BRASILEIROS.A. – PETROBRAS

(Exact name of registrantas specified in its charter)

Brazilian PetroleumCorporation – PETROBRAS

(Translation of Registrant'sname into English)

Avenida Henrique Valadares, 28 – 9th floor 
20231-030 – Rio de Janeiro, RJ
Federative Republic of Brazil

(Address of principalexecutive office)

Indicate by check markwhether the registrant files or will file annual reports under cover Form 20-F or Form 40-F. 

Form 20-F ___X___ Form40-F _______

Indicate by check markwhether the registrant by furnishing the information contained in this Form is also thereby furnishing the information to the Commissionpursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934.

Yes _______ No___X____

Petrobras informs about 3Q25 results

—

Rio de Janeiro, October 08, 2025 –PetróleoBrasileiro S.A. – Petrobras informs that it will release its 3Q25 Production and Sales Report on October 24, 2025, and its 3Q25Financial Results on November 6, 2025, both after the markets close.

On November 7, 2025, a webcast will beheld to present the company's results for the third quarter of 2025. The event will be presented in Portuguese and will have simultaneoustranslation into English.

www.petrobras.com.br/ir

For more information:

PETRÓLEO BRASILEIRO S.A. – PETROBRAS| Investor Relations

Email: petroinvest@petrobras.com.br/acionistas@petrobras.com.br

Av. Henrique Valadares, 28 – 9th floor –20231-030 – Rio de Janeiro, RJ.

Tel.: 55 (21) 3224-1510/9947

This document may contain forecasts within the meaningof Section 27A of the Securities Act of 1933, as amended (Securities Act), and Section 21E of the Securities Trading Act of 1934, as amended(Trading Act) that reflect the expectations of the Company's officers. The terms: "anticipates", "believes", "expects","predicts", "intends", "plans", "projects", "aims", "should," and similarterms, aim to identify such forecasts, which evidently involve risks or uncertainties, predicted or not by the Company. Therefore, futureresults of the Company's operations may differ from current expectations, and the reader should not rely solely on the information includedherein.

SIGNATURES

Pursuant to the requirements 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: October 8, 2025

PETRÓLEO BRASILEIRO S.A–PETROBRAS

By: /s/ Fernando Sabbi Melgarejo

______________________________

Fernando Sabbi Melgarejo

Chief Financial Officer and Investor RelationsOfficer