Regulation of Services
The public water supply and sewage services provided by the Company in municipalities subject to state regulation are regulated and supervised by the Minas Gerais State Regulatory Agency for Water Supply and Sewage Services – Arsae-MG. The Agency was established by State Law No. 18,309/2009, in accordance with the national guidelines established by Federal Law No. 11,445/2007, as amended by Federal Law No. 14,026/2020.
Within the scope of Arsae-MG, tariff regulation seeks to reconcile the economic and financial balance of service provision, tariff affordability, efficiency, universal access to services, and service quality. Tariff revenue is structured based on efficient operating costs, taxes and other obligations, special programs, uncollectible revenues and capital costs, less other revenues recognized by the regulation.
Services are remunerated through differentiated tariffs based on user category, service provided and consumption range. The tariff structure includes a fixed component associated with service availability and a variable component calculated based on billed volume, in cubic meters (m³), in accordance with the rules and tariff tables approved by Arsae-MG.
The current tariff structure comprises eight categories: Social Residential I, Social Residential II, Residential, Commercial, Industrial, Public, Philanthropic Entity and Public Hospital, pursuant to Arsae-MG Resolution No. 217/2025 and the tariff structure methodology applicable to the 3rd Periodic Tariff Review.
Periodic Tariff Review
The periodic tariff review consists of a comprehensive reassessment of the conditions under which services are provided and the market served. The process considers, among other factors, efficient operating costs, taxes and other obligations, special programs, uncollectible revenues, capital costs, other revenues, the X Factor, tariff incentives, financial components and the tariff structure.
In the 3rd Periodic Tariff Review, Arsae-MG established the tariffs for the 2026–2029 tariff cycle. The resulting tariffs became effective on January 22, 2026. The Average Tariff Effect, which represents the average change in the tariffs charged to users, was 6.56%, pursuant to Arsae-MG Resolution No. 217/2025 and CRE Technical Note No. 16/2025.
Annual Tariff Adjustments
For the tariff cycle from January 2026 to December 2029, annual tariff adjustments follow the methodology established in CRE Technical Note No. 11/2025, updated in December 2025.
In the annual adjustments, base tariffs are updated for inflation and the X Factor. In the current cycle, the X Factor corresponds to the mechanism for sharing productivity gains with users. Following the update of base tariffs, tariff incentives associated with targets for reducing and controlling water losses, universal access to water supply, universal access to sewage services and service quality are taken into account, together with the applicable financial components, to determine the tariffs actually charged to users.
Financial components correspond to temporary adjustments or compensations, generally related to prior periods, and may increase or reduce the tariffs actually charged. These amounts are not permanently incorporated into base tariffs.
Further information on the regulatory environment, the history of tariff cycles and the rules applicable to the determination of the Company’s tariffs is available in item 1.10.c of the 2026 Reference Form, as well as in the resolutions and technical notes published by Arsae-MG.
The annual tariff adjustment calendar, with the new tariffs scheduled to become effective on January 22, 2027, has been published by Arsae-MG. The calendar sets out all stages of the process, including calculation of the adjustment, delivery of the results to the Company, submission and review of any challenge, and publication of the final result. Click here to view the calendar.
History of Tariff Adjustments and Reviews
The history of the Company’s tariff adjustments and tariff reviews since 2010 is presented below.
| MONTH OF APPROVAL | AVERAGE TARIFF IMPACT | EVENT | BEGINNING | RESOLUTION | TECHNICAL NOTES |
| 12/2025 | +6.56% | 3rd Periodic Tariff Review | January 22, 2026 | Resolution No. 217/2025 | CRE No. 16/2025 |
| 11/2024 | +6.42% | Tariff Adjustment | January 1, 2025 | Resolution No. 197/2024 | GRT No. 07/2024 |
| 11/2023 | +4.21% | Tariff Adjustment | January 1, 2024 | Resolution No. 185/2023 | GRT No. 06/2023 |
| 11/2022 | +15.70% | Tariff Adjustment | January 1, 2023 | Resolution No. 173/2022 | GRT No. 01/2022 |
| 06/2021 | -1.52% | 2nd Periodic Tariff Review | August 1, 2021 | Resolution No. 154/2021 | CRE No. 14/2021 |
| 06/2020 | +3.04% | Tariff Adjustment | August 1, 2020* | Resolution No. 141/2020 | GRT No. 10/2020 |
| 06/2019 | +8.38% | Tariff Adjustment | August 1, 2019 | Resolution No. 127/2019 | GRT No. 07/2019 |
| 06/2018 | +4.31% | Tariff Adjustment | August 1, 2018 | Resolution No. 111/2018 | GRT No. 09/2018 |
| 06/2017 | +8.69% | 2nd Stage of the Periodic Tariff Review | July 30, 2017 | Resolution No. 96/2017 | CRFEF No. 69/2017 |
| 04/2016 | +13.90% | 1st Stage of the Periodic Tariff Review | May 13, 2016 | Resolution No. 82/2016 | CRFEF No. 30/2016 |
| 04/2015 | +15.04% | Tariff Adjustment | May 13, 2015 | Resolution No. 64/2015 | CRFEF No. 02/2015 |
| 04/2014 | +6.18% | Tariff Adjustment | May 13, 2014 | Resolution No 49/2014 | CRFEF No. 02/2014 |
| 04/2013 | +5.25% | Tariff Adjustment | May 13, 2013 | Resolution No. 35/2013 | CRFEF No. 004/2013 |
| 04/2012 | +4.34% | Tariff Adjustment | May 13, 2012 | Resolution No. 20/2012 | NT No. 005/2012 |
| 03/2011 | +7.02% | Tariff Adjustment | April 23, 2011 | Resolution No. 04/2011 | NT No. 004/2011 |
| 01/2010 | +3.96% | Tariff Adjustment | March 1, 2010 | Resolution No. 001/2010 | NT No. 003/2010 |
*The application of this tariff adjustment was postponed for 90 (ninety) days from August 1, 2020.
Public Hearings and Consultations
Arsae-MG holds public hearings and consultations to obtain technical and social input for its decision-making process.
Click here to view the 2026 public consultations and hearings.
Legislation
Federal Legislation
Federal Law No. 14,026/2020*: updates the legal framework for basic sanitation and amends Federal Law No. 11,445/2007 to improve the structural conditions for basic sanitation in Brazil.
Federal Law No. 11,445/2007*: establishes national guidelines for basic sanitation and provides for related matters.
Federal Decree No. 7,217/2010*: regulates Federal Law No. 11,445/2007, which establishes national guidelines for basic sanitation.
Federal Law No. 11,107/2005*: sets forth general rules for contracting public consortia and provides for related matters.
Federal Decree No. 6,017/2007*: regulates Federal Law No. 11,107/2005, which sets forth general rules for contracting public consortia.
Federal Law No. 8,987/1995*: provides for concession and permission regimes for the provision of public services under Article 175 of the Federal Constitution and provides for related matters.
State Legislation
State Law No. 18,309/2009*: sets forth rules applicable to water supply and sewage services, establishes Arsae-MG and provides for related matters.
State Decree No. 47,884/2020*: : contains the regulation governing Arsae-MG.
* Portuguese Only