As a rule, a player or a team official sent off from the field of play and/or its immediate surrounds, including the technical area, is automatically suspended for the next match in the competition. In case of serious offences, the UEFA Control, Ethics and Disciplinary Body is entitled to augment this punishment, including by extending it to other competitions.
In case of repeated cautions:
in the qualifying competition, players and team officials are suspended for the next competition match after the second and fourth caution;
in the final tournament, players and team officials are suspended for the next competition match after the second caution and any subsequent even-numbered caution (e.g., fourth, sixth, etc.).
Cautions that have not resulted in a suspension expire on completion of the elite round and are not carried forward to the final tournament.
In the final tournament, cautions that have not resulted in a suspension expire on completion of the group stage and are not carried forward to the semi-finals nor to any FIFA U-20 World Cup play-off matches.
Cautions and pending yellow-card suspensions expire on completion of the competition.