2017–18 Segunda División B

The 2017–18 Segunda División B season was the 41st since its establishment. The first matches of the season were played on 20 August 2017, and the season ended June 2018 with the promotion play-off finals.

Overview before the season
80 teams will join the league, including four relegated from the 2016–17 Segunda División and 18 promoted from the 2016–17 Tercera División. The composition of the groups was determined by the Royal Spanish Football Federation, attending to geographical criteria.


 * Relegated from Segunda División:
 * UCAM Murcia
 * Mallorca
 * Elche
 * Mirandés


 * Promoted from Tercera División:


 * Atlético Madrid B
 * Deportivo Aragón
 * Badajoz
 * Cerceda
 * Écija
 * Fabril
 * Formentera
 * Gimnástica Segoviana
 * Las Palmas Atlético
 * Lorca Deportiva
 * Olot
 * Ontinyent
 * Peña Deportiva
 * Peña Sport
 * Peralada
 * Rápido de Bouzas
 * Real Betis B
 * Sporting Gijón B
 * Talavera de la Reina
 * Unión Adarve
 * Vitoria

Average attendances
This is a list of attendance data of the teams that give an official number. They include playoffs games:

Notes: 1: Team played last season in Segunda División. 2: Team played last season in Tercera División.
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