How elections work in Brazil

Brazil holds general elections every four years, always in October. All voting is done electronically via a system of standalone machines that have been in use since 1996 and achieved full national coverage by 2000.

The machines are not connected to the internet and use multiple layers of encryption and digital signatures to prevent tampering. No cases of voter fraud have ever been documented in the system.

In 2026, Brazilians will elect a president, 27 state governors, all 513 lower-house members, and renew 54 of the Senate’s 81 seats.

The president and governors are elected by a simple majority, but with a catch. If no candidate wins more than 50% of valid votes in the first round (always held on the first Sunday of October), the top two face each other in a runoff (on the last Sunday of October).

As blank and spoiled ballots are excluded from the count of “valid” votes, a candidate can win without a majority of the total electorate. Every valid vote carries equal weight, as Brazil has no electoral college system.

The 513 seats in the House are distributed among Brazil's 27 states, with the bench size of each reflecting its population. No state gets fewer than eight seats, but as an example, São Paulo, the country’s most populous, holds 70 seats.

The number of votes received for each state is divided by the number of seats up for grabs, resulting in what is called the “electoral quotient.” Each party (or alliance of parties) that receives a total number of votes greater than or equal to the quotient has the right to representation in the lower house.

For instance, if 30 million people in São Paulo cast votes for lower house candidates, that state’s electoral quotient would be roughly 430,000. If Party X received a total of 3 million votes in São Paulo, it would have the right to six of the state’s House seats. Brazil uses an open-list system to decide who fills those seats, in which the candidates with the most votes from each party (or federation) are elected.

The system is designed to reflect ideological diversity, though its complexity — and the phenomenon of high-profile candidates pulling lesser-known running mates into office — has made it one of the more debated features of Brazilian democracy.

Brazil's 81 senators serve eight-year terms, with seats renewed in staggered cycles. In some elections, one-third of the Senate is up for grabs; in others, two-thirds. In 2026, 54 seats will be contested (two per state). Unlike the lower house, Senate races use a first-past-the-post system: the candidate with the most votes in each state wins, regardless of margin.

Brazil's electoral justice system consists of a specialized branch of the country's judiciary dedicated to overseeing the entire election process — from voter registration to the certification of the final results — with a constitutional mandate to ensure that all elections are free and fair.

Unlike the US, where elections are administered by executive-branch agencies at the state level, Brazil entrusts this function to a permanent judicial body, intended to shield the process from partisan interests. As a result, the same institution that organizes elections also adjudicates disputes arising from them. 

Each of the country’s 27 states has its own regional electoral court, all of which operate under the umbrella of the national-level Superior Electoral Court (TSE). The TSE has seven titular justices, including three from the Supreme Court — one of whom serves as chief electoral justice — and seven alternates.

The consolidation of administrative, judicial, normative and advisory powers into a single specialized institution means that Brazil's electoral system operates under tight, unified legal oversight at every stage — before, during and after election day. Rather than dispersing these functions across ministries, agencies and ordinary courts, the Brazilian model establishes a single body that is accountable for the integrity of the entire process.

For a country of Brazil's size and democratic complexity — 215 million people, a multi-party system and elections held simultaneously across thousands of municipalities — that institutional coherence means elections are conducted the same way all over the country, from the wealthiest neighborhoods of São Paulo to the most remote areas of the Amazon rainforest, and everywhere in between.

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