Bill 170/2026 and a single tariff adjustment index

Until now the annual adjustment of electricity tariffs has followed a methodology that varies by concession holder, with no single national index. Bill 170/2026, approved on 2 September 2026 by the Senate Infrastructure Services Committee, proposes consumer inflation as the cap on adjustments across the country and provides for suspension of the contract of any distributor that exceeds the limit.

The variable left out is the date on which the rule takes effect. According to the legislative record of Bill 170/2026 in the Federal Senate, consulted on 4 September 2026, the bill reached the Economic Affairs Committee on 3 September awaiting a rapporteur, is proceeding under terminative decision subject to appeal to the Plenary and, if approved, goes to the Chamber of Deputies.

Without an effective date, the 2027 tariff cycle continues to be calculated under the current rule. Distributors and investors price investment on two adjustment regimes at the same time, and this dual assumption raises the cost of capital before any change in tariffs.

The effect of Bill 170/2026 on concession contracts will be defined by its effective date.