Although the window officially shuts at 23:00 BST, some transfers may still be finalised shortly after.
To make this possible, clubs must file a deal sheet with the Premier League by 21:00 BST, which, with the league’s approval, grants an extra two hours beyond the deadline to complete a late move.
After the window closes, clubs are required to submit their registered squad to the Premier League.
There is no publicly announced cut-off for this, but it’s generally understood to be about a week after the window ends.
Squads cannot exceed 25 players aged over 21, and no more than 17 senior players may be classed as non–locally trained.