From the 2004/05 season, the UEFA Cup adopted a new format that including a group stage alongside the traditional two-legged format, with the final continuing as a single match.

Altered format
Two qualifying rounds and the first round proper open the competition, at which point 40 clubs advance to the group stage. This part of the competition comprises eight groups of five teams with two matches at home and two matches away for each team in each group. The winners, runners-up and third-placed team advance to the knockout phase, at which point they are joined by the eight clubs which finish in third place in each of the groups in the UEFA Champions League group stage.

Knockout stage
From this point, the 32 clubs embark on a knockout competition, playing two matches against each other on a home and away basis. The club scoring the greater aggregate of goals qualifying for the next round. In the event of both teams scoring the same number of goals, the team which scores more goals away qualifies.

Final
The final is decided by a single match.