The APC has been the main opposition party in Sierra Leone since 4 April 2018 when Julius Maada Bio of the SLPP won the 2018 presidential elections, though it maintains a majority in parliament.

The APC lost power on 4 April 2018, with its flagbearer Samura Kamara losing the presidential election to Bio.

The APC is very popular and receives large majority support in almost all of the northern districts of Sierra Leone with strong ties to the Temne and some Limba people.

Its candidate in the presidential elections, Ernest Bai Koroma, won 22.3% of the vote; he was defeated by Ahmad Tejan Kabbah of the Sierra Leone People's Party (SLPP).

In the parliamentary election, held concurrently with the presidential first round, the APC won 59 out of 112 seats and became the largest party in Parliament.