Next Brazil Senate Election: Most Seats Held

The next federal Senate election is scheduled to take place in Brazil on October 4, 2026, in which two-thirds of the Senate’s 81 seats will be contested. This market will resolve according to the political party that holds the greatest number of seats in the next Brazilian Senate as a result of the next Brazilian Senate election. All seats, not only the ones contested in the next Brazilian Senate election, will be considered. In the event of a tie between multiple parties for the most seats held, this market will resolve in favor of the party whose listed abbreviation appears first in alphabetical order. This market's resolution will be based solely on the number of seats held by the named party in the Brazilian Senate as a result of the next Brazilian Senate election, not by any federation or coalition it may be a part of. If the result of this election isn't known definitively by June 30, 2027, 11:59 PM ET, the market will resolve to "Other". This market will resolve based on the result of the election, as indicated by a consensus of credible reporting. If there is ambiguity, this market will resolve based solely on the official results as reported by the Brazilian government, specifically the Superior Electoral Court (Tribunal Superior Eleitoral, TSE) (e.g., www.tse.jus.br/eleicoes/resultados-eleicoes) or the Brazilian Senate (https://www25.senado.leg.br/web/senadores/em-exercicio/-/e/por-partido).

How trading works

Polymarket uses a central limit order book (CLOB) model — you can buy or sell shares of any outcome at the current market price, or place limit orders. Prices represent implied probability: a $0.65 contract means the market prices a 65% chance of that outcome.