Voters will be electing 127 of the 257 members of the lower house Chamber of Deputies and 24 of the 72 members of the upper house Senate.
Members of the Chamber of Deputies are elected by proportional representation in 24 multi-member constituencies based on the provinces (plus the City of Buenos Aires). Seats are allocated using the d'Hondt method, with a 3% electoral threshold. Members serve four-year terms.
Members of the Senate are elected in the same 24 constituencies, with three seats in each. The party receiving the most votes in each constituency wins two seats, with the third seat awarded to the second-placed party. Senators serve six-year terms.
Argentina has a population of around 46 million and 35.8 million registered voters. In the 2023 parliamentary elections, voter turnout was 77%.