A total of 22 teams contested the league: 15 returning from the 2016–17 Serie B season, 4 promoted from 2016–17 Lega Pro (Cremonese, Venezia, Foggia, Parma), and 3 relegated from 2016–17 Serie A (Empoli, Palermo, Pescara).
On August 13, 2018, the FIGC decided to reduce the chronic financial instability of the league halting re-elections of clubs.
Those winning teams advanced to the two-legged final, where the winner was promoted to play in Serie A the following season.
In the two-legged rounds, the higher seeded team played the second game at home.
In the case of a tie on aggregate, the higher placed team from the regular season were declared the winners.