The final, originally scheduled at the Stade de Marseille,[2] occurred on 22 May 2021 at Twickenham Stadium.

[5] Due to the COVID-19 pandemic delaying the end of the previous tournament twenty-four clubs from the three major European domestic and regional leagues would compete in the Champions Cup in a one-year exceptional basis.

[10][11] However, the Pro14 announced in June 2020 that their European representation would be decided by standings after round 13, the final series of games before the hiatus.

Note: Placing shown in brackets, denotes standing at the end of the regular season for their respective leagues, with their end of season positioning shown through CH for Champions, RU for Runner-up and SF for losing Semi-finalist.

Originally, four rounds of inter-pool play was to be followed by a knockout stage, featuring two-legged quarterfinals, and single leg semi-finals and final (to be held in Marseille on 22 May 2021).

Teams which won both their matches and were not awarded points due to COVID cancellations would be guaranteed home advantage.