SEC Form 6-K filed by TIM S.A.

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549

FORM 6-K

REPORT OF FOREIGN PRIVATE ISSUER
PURSUANT TO RULE 13a-16 OR 15d-16
UNDER THE SECURITIES EXCHANGE ACT OF 1934

Date of Report: July 22, 2025

Commission File Number: 001-39570

TIM S.A.
(Exact name of Registrant as specified in its Charter)

João Cabral de Melo Neto Avenue, 850 – North Tower – 12^th floor
22775-057 Rio de Janeiro, RJ, Brazil
(Address of principal executive office)

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

Form 20-F ☒ Form 40-F ☐

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1).

Yes ☐ No ☒

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7).

Yes ☐ No ☒

TIM S.A.

Publicly-Held Company

CNPJ/MF 02.421.421/0001-11

NIRE 333.0032463-1

MINUTES OF THE BOARD OF DIRECTORS’ MEETING

HELD ON JULY 22^ND, 2025

DATE, TIME AND PLACE: July 22^nd, 2025, at 10.20 a.m., at the head office of TIM S.A. (“Company”), domiciled at Avenida João Cabral de Mello Neto, 850, Torre Sul, 13° floor, Barra da Tijuca, in the city and State of Rio de Janeiro.

PRESENCE: The Board of Directors’ Meeting of the Company was held at the date, time and place mentioned above, with the presence of Messrs. Nicandro Durante, Adrian Calaza, Alberto Mario Griselli, Alessandra Michelini, Claudio Giovanni Ezio Ongaro, Flavia Maria Bittencourt, Gesner José de Oliveira Filho, Gigliola Bonino, Herculano Aníbal Alves, either in person or by means of audio or videoconference, as provided in the 2^nd paragraph of Section 25, of the Company’s By-laws. Justified absence of Mr. Leonardo de Carvalho Capdeville.

BOARD: Mr. Nicandro Durante – Chairman; and Mrs. Fabiane Reschke – Secretary.

AGENDA: (1) To acknowledge on the activities carried out by the Statutory Audit Committee; and (2) To resolve on the payment proposal of the Company’s interest on shareholders’ equity (“IE”).

RESOLUTIONS: Upon the review of the material presented and filed at the Company’s head office, and based on the information provided and discussions of the subjects included on the Agenda, the Board Members, unanimously by those present and with the abstention of the legally restricted, decided to register the discussions as follows:

(1) Acknowledged on the activities carried out by the Statutory Audit Committee (“CAE”) at its meeting held on July 22^nd, 2025, as per Mr. Gesner José de Oliveira Filho, Coordinator of the CAE.

(2) Approved based on the Section 46, 3^rd and 4^th paragraphs, of the Company’s By-laws, and on the favorable opinion of the Fiscal Council, the distribution of R$ 320,000,000.00 (three hundred and twenty million reais) as Interest on Shareholders’ Equity ("IE"), at R$0.1323151001 (zero point one, three, two, three, one, five, one, zero, zero, one cents) of gross value per share. The payment will be made until October 21^st, 2025, considering the date of July 25^th, 2025, as the date for identification of shareholders entitled to receive such values. Therefore, the shares acquired after said date will be traded ex-direito of IE distribution. The withholding of Income Tax will be of 15% (fifteen percent) on the occasion of the credit of the IE, except for the shareholders who have differentiated taxation or who are exempt from said taxation. The gross amount per share may be modified due to the variation in the number of treasury shares.

CONT. OF MINUTES OF THE BOARD OF DIRECTORS’ MEETING OF TIM S.A.

July 22^nd, 2025

CLOSING: With no further issues to discuss, the meeting was adjourned, and these minutes drafted as summary, read, approved and signed by all attendees Board Members.

I herein certify that these minutes are the faithful copy of the original version duly recorded in the respective corporate book.

Rio de Janeiro (RJ), July 22^nd, 2025.

FABIANE RESCHKE

Secretary

2

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.