A total of 22 teams were contesting the league: 15 returning from the 2015–16 season, 4 promoted from Lega Pro, and 3 relegated from Serie A.
According to the regulations, third-placed Frosinone would have avoided the play-offs if they had ended the regular season 10 points clear of fourth place.
However, in the last round, Perugia and Benevento won their matches to leave the gap at nine points.
The higher placed team played the second leg of the promotion playoff at home.
Source:[18] Source: [19]Notes:1: Team played last season in Serie A.2: Team played last season in Lega Pro.