The top four placed teams from each group in the Segunda División B played in the Liguilla de Ascenso.
Each liguilla contained one team from each of the four regular season groups.
The winner of each tie was determined by aggregate score, with draws being separated by the away goals rule or a penalty shoot-out where necessary.
The regular season finished on the 27 May and the play-offs began on the 3 June.
The two losers of this tournament will play another tie, which will decide the team that will be relegated to the 2006-07 Tercera División.