Before the start of season 2005/2006 the Bulgarian Football Union decided to divide B Group in two groups - "West B Group" and "East B Group" with 14 teams in each group. Every team plays 13 matches as home team and 13 matches as away team. The two champions of the groups were directly promoted to A Group and the two teams that finished in second place in their group played a play-off for winning the final third place for promotion in A Group. On May 19, 2008 the two groups were extended to 16 teams. For season 2010/2011 the two groups were reduced again with 12 teams in each.