Bolsonaro left the party in 2019 after disagreements with its president, Luciano Bivar, and then founded Alliance for Brazil.

[11] PSL was originally founded on 30 October 1994 by businessman Luciano Bivar as a social liberal party.

In 2015, PSL underwent a reform led by the internal social liberal wing Livres, with names such as political scientist Fábio Ostermann [pt] and journalist Leandro Narloch reinforcing the party's affiliation with social liberal policies.

Bolsonaro eventually became PSL's nominee for the 2018 presidential election, exceeding polling forecasts to receive 46% of the popular vote in the first round.

[19] It also became the largest single party in the legislative assemblies of both Rio de Janeiro and São Paulo.

[20][21] On 28 October 2018, Bolsonaro was elected president with 55.13% of the votes, defeating Workers' Party's Fernando Haddad.