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

Yes ______ No ___X___

COMPANHIA DE SANEAMENTO BÁSICO DO ESTADO DE SÃO PAULO – SABESP

PUBLICLY HELD COMPANY

Corporate Taxpayer’s ID (CNPJ): 43.776.517/0001-80

Company Registry (NIRE): 35.3000.1683-1

CALL NOTICE

Companhia de Saneamento Básico do Estado de São Paulo - Sabesp (“Company”), located at Rua Costa Carvalho, nº 300, in the City and State of São Paulo, hereby invites its Shareholders, according to paragraph 1 of article 5 of its Bylaws, to participate in the Company’s Annual and Extraordinary Shareholders’ Meetings (“AESM” or “Meetings”), to be held on April 28, 2022, at 11:00 am, in an exclusively digital format, through the Zoom Meetings platform, according to CVM Instruction 481, of December 17, 2009, as amended by CVM Instruction 622, of April 17, 2020 (“CVM Instruction 481”), to resolve on the following agenda:

ANNUAL SHAREHOLDERS’ MEETING

EXTRAORDINARY SHAREHOLDERS' MEETING

change article 20 to reorganize specific authorities of the Executive Board by (c.1) excluding subitems “d” and “g” of item X of paragraph two, (c.2) transferring the provisions of items “d” and “g” of item of X paragraph two to items VIII and IX of paragraph four, and (c.3) excluding the wording previously in effect of item VIII.

Information to the Shareholders:

The Meetings will be held exclusively online, according to CVM Instruction 481, and Shareholders are allowed to participate (i) in person or by a proxy, through the electronic platform at the time defined for the AESM, or (ii) by sending a voting instruction before the AESM, through a Remote Voting Form.

The rules and procedures for shareholders’ participation in the General Meetings are detailed in the Manual to Participate in the Meeting, and the information about the matters to be resolved at the Meetings are detailed in the Management Proposal (Portuguese only), both of which are available on the Company’s Investor Relations website (https://ri.sabesp.com.br/), and on the websites of B3 (www.b3.com.br) and the Brazilian Securities and Exchange Commission (https://www.gov.br/cvm/pt-br).

Shareholders who wish to participate in the Meetings via the digital platform made available by the Company shall send the documents necessary for participation, as described in the Manual to Participate in the Meeting, until 11:00 a.m. of April 26, 2022, to the Company’s headquarters, at Rua Costa Carvalho, nº 300, in the City and State of São Paulo, or email them to sabesp.ri@sabesp.com.br, to the care of the Investor Relations Department (Superintendência de Captação de Recursos e Relações com Investidores).

It should be noted that the personal data and documents requested for accreditation and participation in the Meetings will be used exclusively for this purpose according to article 7, item II, of Law 13,709/2018 (compliance with legal obligation), based on Brazilian Corporation Law and correlating regulations.

After analyzing the documents, the Company will email Shareholders with the access link to the AESM, including specific access instructions. The access to the AESM will be restricted to Shareholders and/or their representatives or proxies accredited within the term defined by the Company, who will receive an individual invitation with specific instructions to access the digital platform.

II. Participation through Remote Voting Form

If Shareholders decide to participate in the AESM through a remote voting form, they must (a) send filling instructions of the Remote Voting Form to service providers for the collection and transmission of instructions for filling out these documents (custody agents or bookkeeping agent of the shares issued by the Company), provided that such instructions are received within up to seven (7) days before the Meetings; or (b) send the Remote Voting Form directly to the Company, provided that the instructions are received within seven (7) days before the AESM, and any Remote Voting Forms received by the

Company after this deadline will be disregarded. The submission of the Remote Voting Form to the custodian agent shall comply with the applicable rules and procedures indicated by them, while the Remote Voting Forms directly sent to the Company shall be accompanied by the documents indicated in the Manual for Participation in the Meeting and addressed to the Company’s headquarters, at Rua Costa Carvalho, nº 300, in the City and State of São Paulo, or emailed to sabesp.ri@sabesp.com.br, to the care of the Investor Relations Department (Superintendência de Captação de Recursos e Relações com Investidores).

Shareholders who send their Remote Voting Forms may participate in the Meetings via the digital system. However, should they exercise their voting right at the respective Meeting, their Remote Voting Forms will be fully disregarded and the votes cast at the Meeting will be considered valid.

III. Requests for a Multiple Vote

To request the adoption of a multiple vote for the election of the Board of Directors’ members, according to CVM Instruction 165, of December 11, 1991, as amended, the applicants must represent at least 5% of the Company’s voting capital and may exercise this option up to 48 hours before the Meetings.

The Company emphasizes the importance that any requests for a multiple vote be made in advance, to facilitate their processing by the Company and the participation of other Brazilian and foreign Shareholders.

The other rules and procedures for shareholder participation in the Meetings are detailed in the Manual to Participate in the Meeting, available on the Company’s Investor Relations website (https://ri.sabesp.com.br) and the website of the Brazilian Securities and Exchange Commission (“CVM”) (www.cvm.gov.br).

São Paulo, March 24, 2022.

Mario Engler Pinto Junior

Chairman of the Board of Directors