The electoral quotient is the number of votes a seat is worth in an election for deputy or city councillor: the sum of the valid votes (for candidates and party lists; blank and null votes do not count) divided by the number of seats.
The calculation, step by step
1. The electoral quotient. Valid votes ÷ seats. It is what a seat is worth in that election (Article 106 of the Electoral Code, in Portuguese).
2. The party quotient. The votes of each party or federation (the sum of the votes for its candidates and for the party list) ÷ the electoral quotient. The result, without the fraction, is the number of seats the party wins in this first round (Art. 107).
3. Who takes the seats. Within each party, the candidates with the most votes get in, in order of votes. To win a seat this way, the candidate needs at least 10% of the quotient in their own votes (Art. 108).
4. The leftover seats. The division is almost never exact, and the remaining seats go to the highest averages, in rounds. In the first round of leftover seats, only parties with at least 80% of the quotient and candidates with at least 20% of it compete (Law 14,211/2021). When no one else meets those two requirements, the last round is open to all parties and candidates, with no threshold at all: that is what Brazil's Supreme Federal Court (STF) ruled in February 2024, and in 2025 it applied the same rule to the 2022 election as well.
A real example: city councillors in Campinas, 2024
Valid votes: 530,566. Seats: 33. Quotient: 530,566 ÷ 33 = 16,078 votes. Even so, the last councillor elected got in with 3,268 votes, and the first one left out had 4,924: more votes than the last person elected, but from a party that did not add up enough votes for one more seat. See the Campinas election.
And in a statewide election: federal deputies from São Paulo, 2022
Valid votes: 23,302,342. Seats: 70. Quotient: 332,891 votes per seat. The last person elected got 71,754 votes, about 22% of the quotient. See the São Paulo election.
Coalition and federation
Until 2018 (2016 in the cities), parties could join in a coalition just for the election, and their combined votes counted as a single party's. Coalitions in deputy and city councillor elections ended in 2020. Since 2022 there is the federation: a bond of at least four years in which the parties count as one, for the quotient too.
See the quotient and the last person elected in each state in how many votes it takes to elect a deputy and in the state capitals in how many votes it takes to elect a city councillor.