A total of 20 teams have been confirmed to play in the 2020 Peru Primera Division, an increase of two teams from the previous season. The top sixteen teams in the 2019 season will take part, along with 2019 Liga 2 (Peru) champions Cienciano, Copa Perú champions Carlos Stein, and the top two teams of the promotion play-offs (Atlético Grau and Deportivo Llacuabamba). The season will be divided into three stages: Torneo Apertura (Stage 1), Torneo Clausura (Stage 2), and the Playoffs. The first and second stages were two Apertura and Clausura tournaments, later rebranded as Stage 1 and Stage 2, respectively. In the Apertura tournament, each team played the other teams once for a total of 19 games. Prior to the onset of the COVID-19 pandemic, the Clausura tournament was scheduled to be played in a similar way to the Apertura, with reversed fixtures, however, its format was altered due to the 5-month suspension of the league. For the Clausura, the 20 teams were split into two groups of 10 according to their final placement in the Apertura. Teams will play the other teams in their group once, with the winners of both groups playing a final to decide the Clausura winners. Points earned during the Apertura did not carry over during the Clausura. The winners of the Apertura and Clausura stages will qualify to the playoffs along with the top two teams of the aggregate table at the end of the season. The playoffs to decide the national champion will be contested by four teams, which will play two semifinals with the winners playing the final. In every stage of the playoffs, the teams with the most points on the aggregate table will choose which leg they play as the home team. If the teams are tied in points after the two legs of the final, a third match on neutral ground will be played to decide the national champion. If a team wins both the Apertura and Clausura, the playoffs will not be played and that team will be declared as champion. Qualification to international competitions will be as follows: the four playoff qualifiers (or the top four teams of the aggregate table should the playoffs are contested by a lower amount of teams) will qualify for the 2021 Copa Libertadores, while the next three best teams in that table will qualify for the 2021 Copa Sudamericana, with a fourth berth being allocated to the 2020 Copa Bicentenario winners. With the cancellation of the Copa Bicentenario due to the COVID-19 pandemic, the Copa Sudamericana berth allocated to its winner was transferred to the eighth best team in the aggregate table. The four teams with the fewest points in the aggregate table at the end of the season were to be relegated, unless the Copa Perú was not played this season, in which case only three teams would be relegated. If the Liga 2 (Peru) was not played this season either, only two teams would be relegated. Eventually, only the Copa Perú was confirmed to not be held this season, with which three teams will be relegated from Peru Primera Division at the end of the season.