As of December 31, 2025 and December 31, 2024, the disputed amounts receivable between SABESP and the São Paulo State, referring to additional retirement and pension benefits paid (Law No. 4,819/1958), totaled R$ 1,808,631 and R$ 1,685,493, respectively, and an ADA was recognized for the total amount, see Note 10 (c).

The Company recognized an actuarial liability corresponding to additional retirement and pension benefits paid to employees, retired employees, and pensioners of the G0, see Note 25. As of December 31, 2025 and December 31, 2024, the amounts corresponding to such actuarial liability were R$ 2,140,161 and R$ 1,931,145, respectively. For detailed information on additional retirement and pension benefits, see Note 25.

The Company maintains joinder agreements to the PURE Program with public entities operating in the São Paulo State. The purpose of the program is to promote the conscious use of water, granting participating entities a 25% tariff discount, provided that they are in a regular situation of compliance and meet the established goals.

The São Paulo State provides guarantees for some of the Company’s borrowings and financing and does not charge any related fees, see Note 17.

The Company formalized three financing agreements under the State Fund for Water Resources (FEHIDRO). The funds are aimed at the execution of works and sewage services. As of December 31, 2025, the balance of these financings was R$ 938, recorded under the “Other” line in borrowings and financing (R$ 2,799 as of December 31, 2024).

As of December 31, 2025, the Company had an amount of R$ 3,521 (R$ 3,613 as of December 31, 2024) related to land and lent structures under free lease agreements.

The Company sponsors a defined benefit plan (G1 Plan), which is operated and administered by SABESPREV. The net actuarial commitment, recognized until December 31, 2025, was R$ 99,514. As of December 31, 2024, this plan had a surplus of R$ 132,244.

The expenses related to the compensation of key management personnel were as follows:

Águas de Andradina

As of December 31, 2025, the balance of principal and interest was R$ 4,718, recorded under “Other assets” in current assets (R$ 4,007 in current assets as of December 31, 2024), at DI + 3% p.a.

This loan agreement was executed on August 17, 2021 and will be settled with the purchase and sale transaction. See further details in Note 12.

SABESP Olímpia

The Company signed a loan agreement with subsidiary Sabesp Olímpia S/A, making available the necessary funds for the payment of the Fixed Concession Fee to the Municipality, which was a prerequisite for the signing of the water and sewage concession agreement.

The loan agreement, of R$ 170,981, was used for capital increase in SABESP Olímpia in the first quarter of 2025, see Note 12.

According to Article 7 of Law No. 9,361/1996, the controlling shareholder will be reimbursed, upon the privatization, the services of independent audit firms, law firms, opinions, or specialized studies necessary for the privatization.

The amount to be reimbursed by the São Paulo State as of December 31, 2025 was R$ 85,929, recorded under “Other assets” (R$ 99,653 as of December 31, 2024).

In July 2024, Equatorial Participações e Investimentos IV S.A., controlled by Equatorial S.A., acquired shares representing 15% (fifteen percent) of the share capital of SABESP. In December 2024, Equatorial S.A. merged its subsidiary, becoming the direct holder of the equity interest in SABESP. As of December 31, 2025, the balance of dividends and interest on equity payable was R$ 348,402 and (R$ 341,272 as of December 31, 2024).

On August 1, 2025, the Company issued the 36th issue of simple non-convertible unsecured debentures, in the total amount of 2,815,700, with a unit par value of R$ 1, with maturity in 2030 and a yield of IPCA + 9.28% p.a. (See Note 17 (a)). Of these debentures, 2,765,700 were acquired by SABESP Luxembourg (98.22% of the total securities of this issue). This transaction involved entering into a derivative instrument swapping the yield for CDI (see Note 19).