B-Liga (formerly the Danish Women's 1st Division) is the second-highest division of women's football in Denmark.
Until and including the 2006–07 season, the B-Liga comprised 12 teams playing a double round-robin tournament – each team playing each other twice; once home, once away. The champion was promoted to the A-Liga, called Elitedivisionen at the time. The runner-up played a promotion game against the second worst placed team of the A-Liga for a spot in the next season of A-Liga. Meanwhile, the two worst ranked teams were relegated to C-Liga, known as the Women's Denmark Series at the time.
B-Liga was reduced to 10 teams from the 2007–08 season.
From 2013–14 until the 2019–20 season, the B-Liga was expanded to include 16 teams, divided into two groups - East and West - each consisting of eight teams. The highest ranked team from each group would play in the A-Liga qualification play-offs together against the four lowest-ranked teams of A-Liga. The top two teams in the qualification play-offs achieved promotion to the A-Liga.
The 2020–21 B-Liga contained 20 teams, split into four groups of five, each playing a double roun-robin tournament. The top two teams of each group advanced to promotion qualifiers, split into two groups of four. A total of four teams advanced to the qualification play-offs. The remaining 12 teams were in the relegation play-offs, consisting of two groups of six teams each.