Squad Size Requirements
Each team participating in the FIFA World Cup must register a squad of 23 players. This squad includes the 11 players who will start the match on the field, plus 12 substitute players who sit on the bench. Teams must carefully choose their players because once the tournament begins, they cannot add new players to replace injured or suspended teammates.
Player Positions and Selection
The 23-player squad typically includes goalkeepers, defenders, midfielders, and forwards. While FIFA does not require a specific number of players in each position, teams usually select 3 goalkeepers and distribute the remaining 20 players among defenders, midfielders, and forwards based on their tactical strategy. Coaches must balance having enough depth in each position while maintaining team balance.
Substitutions During Matches
During a World Cup match, a team can make up to 3 substitutions to replace players on the field. This means coaches can strategically swap players to manage fatigue, adjust tactics, or respond to injuries. The players who come off the field cannot return to the game once substituted, which makes substitution decisions important.
Squad Submission and Changes
Teams must submit their final 23-player squad approximately 10 days before the World Cup tournament begins. After this deadline, the squad is locked in, and teams cannot make changes except in cases of serious injury. If a player gets injured before a match, that player must be replaced from within the existing squad rather than bringing in a new player.
Recent Tournament Variations
While 23 players is the standard size, FIFA has occasionally adjusted this number for specific tournaments. For example, during the 2022 FIFA World Cup in Qatar, FIFA allowed teams to submit preliminary squads of 55 players, from which they selected their final 23-player squad. It is important to check the specific rules for each World Cup tournament. 
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