A total of 64 teams from at least 32 of the 55 UEFA member associations may enter the 2020–21 UEFA Youth League. They are split into two sections, each with 32 teams:
Domestic Champions Path: The youth domestic champions of the top 32 associations according to their 2019 UEFA country coefficients enter the Domestic Champions Path. If there is a vacancy, it is first filled by the title holders should they have not yet qualified, and then by the youth domestic champions of the next association in the UEFA ranking.
In early April 2020, UEFA announced that due to the COVID-19 pandemic, the deadline for entering the tournament had been postponed until further notice. All teams in italics are declared champions or selected to play by the national association following an abandoned season due to the COVID-19 pandemic in Europe, and are subject to approval by UEFA as per the guidelines for entry to European competitions in response to the COVID-19 pandemic. ;Notes Associations without any participating teams
Squads
Players must be born on or after 1 January 2002, with a maximum of five players born between 1 January 2001 and 31 December 2001 allowed in the 40-player squad, and a maximum of three of these players allowed per each match.
Schedule
The schedule of the competition is as follows. The tournament would originally have started in September 2020, but had been delayed to October due to the COVID-19 pandemic in Europe which caused the group stage of the 2020–21 UEFA Champions League to be postponed.
For the UEFA Champions League Path group stage, in principle the teams play their matches on Tuesdays and Wednesdays of the matchdays as scheduled for UEFA Champions League, and on the same day as the corresponding senior teams; however, matches may also be played on other dates, including Mondays and Thursdays.
For the Domestic Champions Path first and second rounds, in principle matches are played on Wednesdays ; however, matches may also be played on other dates, including Mondays, Tuesdays and Thursdays.
For the play-offs, round of 16 and quarter-finals, in principle matches are played on Tuesdays and Wednesdays of the matchdays as scheduled; however, matches may also be played on other dates, provided they are completed before the dates specified by UEFA.