The first round of the group stage began on the weekend of 12/13/14/15 October 2017, and the competition ended with the final on 11 May 2018 in Bilbao, Spain.

French side Stade Français were the reigning champions but failed to progress past the quarter-finals after losing to Newcastle Falcons.

Like then, Cardiff Blues were victorious, defeating Gloucester 31–30 with a 78th-minute penalty by Gareth Anscombe to clinch the title.

[3] Semi-finals Play-off final Eight teams were split into two pools of four to compete in the re-branded European Rugby Continental Shield.

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, SF for losing Semi-finalist and QF for losing Quarter-finalist.

[9] In the event of a tie between two or more teams, the following tie-breakers will be used, as directed by EPCR: The eight qualifiers are ranked according to their performance in the pool stage and compete in the quarter-finals which was held on the weekend of 30/31 March 2018.

In lieu of the draw that used to determine the semi-final pairing, EPCR announced that a fixed semi-final bracket would be set in advance, and that the home team would be designated based on "performances by clubs during the pool stages as well as the achievement of a winning a quarter-final match away from home".