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Starting with the 2008–09 season, the four group winners had the opportunity to promote directly and become the overall Segunda División B champion. The four group winners were drawn into a two-legged series where the two winners promoted to the Liga Adelante and entered into the final for the Segunda División B champion. The two losing semifinalists entered the playoff round for the last two promotion spots.
The four group runners-up were drawn against one of the three fourth-placed teams outside their group while the four third-placed teams were drawn against each other in a two-legged series. The six winners advanced with the two losing semifinalists to determine the four teams that entered the last two-legged series for the last two promotion spots. In all the playoff series, the lower-ranked club played at home first. Whenever there was a tie in position (e.g. like the group winners in the Semifinal Round and Final or the third-placed teams in the first round), a draw determined the club to play at home first.
Group Winners promotion play-off
Qualified teams
The draw were held in the RFEF headquarters, in Las Rozas (Madrid), on 11 May 2009, 16:30 CEST.
The aggregate winners will be promoted and qualified to the 2009–10 Segunda División B Final. The aggregate losers will be relegated to the Non–champions Promotion Play–off Second Round.