In addition to the domestic league, Alavés participated in this season's edition of the Copa del Rey. The season covered the period from 20 July 2020 to 30 June 2021, with the late start to the season due to the Covid-19 pandemic in Spain.
The 2020–21 Club Deportivo Tenerife season was the club's 109th season in existence and its eighth consecutive season in the second division of Spanish football.
The 2020–21 UD Almería season was the club's 31st season in existence and the club's sixth consecutive season in the second division of Spanish football.
The competition started on 30 August 2006 and concluded on 23 June 2007 with the Final, held at the Santiago Bernabéu in Madrid, in which Sevilla lifted the trophy for the first time since 1948 with a 1–0 victory over Getafe.