In the Championship, League One, and League Two, clubs are required to register a minimum of eight homegrown players in their squad and name at least seven homegrown players in their matchday squad for league games. 

These regulations, however, are not enforced by the EFL for the FA Cup, EFL Cup, or EFL Trophy, and the Premier League operates under its own separate system.

A player is classified as homegrown if they have been registered with their current club, or any English or Welsh club, for three seasons or 36 months before either their 21st birthday or the end of the season in which they turn 21.

 This definition allows non-English or Welsh nationals to qualify based on where they spent their youth club football. For instance, in Watford's 2-0 win over Charlton Athletic, defenders Mattie Pollock and Marc Bola were the only English players listed in the matchday squad, yet Hector Kyprianou (Cyprus), Jordan Zemura (Zimbabwe), Daniel Bachmann (Austria), Stephy Mavididi (Democratic Republic of Congo), and Amin Nabizada (Afghanistan) were all classified as homegrown due to their youth football background.

Additionally, once EFL clubs submit their squad lists following the summer transfer window, they must list at least one club-developed player per match. 

Failing to do so results in a penalty of one fewer substitute on the matchday bench (reducing the Championship bench from nine to eight, and League One and Two benches from seven to six). 

Across all three EFL divisions, players under the age of 21 are exempt from counting toward squad lists, and goalkeepers are excluded from squad lists in League One and League Two.