The 2018–19 Campeonato de Portugal was the sixth season of Portuguese football's new third-tier league, since the merging of the Segunda Divisão and Terceira Divisão in 2013, and the fourth season under the current Campeonato de Portugal title.
A total of 72 teams competed in this division, which began in August 2018 and ended in June 2019.
In the first stage, the 72 clubs will be divided in four series of 18 teams, according to geographic criteria.
In each series, teams play against each other in a home-and-away double round-robin system.
The winners and the runners-up of the 4 Series were qualified to the Promotion Play-offs, where the winning team and the runner-up were promoted to 2019–20 LigaPro.