Overview

• The first round is scheduled for 4 October 2026 with a possible runoff on 25 October, and inaugurations will occur on 5–6 January 2027 under a 2021 amendment.
• The electoral court opened the voting‑machine source code on 2 October 2025 and set a public testing program for December 2025 and a confirmation test in May 2026.
• The constitutional principle of electoral anteriority blocks rule changes within a year of voting, and the TSE has until 5 March 2026 to finalize implementing regulations.
• Key deadlines include voter registration closing on 6 May 2026, party statutes and candidate domicile/renunciation due about six months before the vote, conventions from 20 July to 5 August, candidate registration by 15 August, and campaign start on 16 August.
• Poll aggregates now put President Luiz Inácio Lula da Silva as the favorite despite high rejection rates reported by recent surveys, while parties face tougher thresholds for access to radio/TV time and public funds plus minimum 30% allocations of campaign resources for women and for Black candidates.