Head to Head
| European Rugby Champions Cup | 2021/12/12 17:30 | Castres v Harlequins | W | 18-20 |
| European Rugby Champions Cup | 2015/01/24 13:00 | Castres v Harlequins | W | 19-47 |
| European Rugby Champions Cup | 2014/10/17 18:45 | Harlequins v Castres | W | 25-9 |
Home History
| European Rugby Champions Cup | 2022/01/14 20:00 | Cardiff Blues v Harlequins | W | 33-36 |
| Premiership Rugby | 2022/01/08 15:00 | Harlequins v Exeter Chiefs | W | 14-12 |
| Premiership Rugby | 2022/01/02 15:00 | Gloucester v Harlequins | W | 17-20 |
| Premiership Rugby | 2021/12/27 17:00 | Harlequins v Northampton | W | 41-27 |
| European Rugby Champions Cup | 2021/12/18 13:00 | Harlequins v Cardiff Blues | W | 43-17 |
| European Rugby Champions Cup | 2021/12/12 17:30 | Castres v Harlequins | W | 18-20 |
| Premiership Rugby | 2021/12/05 15:00 | Leicester v Harlequins | L | 16-14 |
| Premiership Rugby | 2021/11/27 15:00 | Harlequins v London Irish | L | 19-22 |
Away History
| European Rugby Champions Cup | 2022/01/14 20:00 | Castres v Munster | L | 13-16 |
| French Rugby Championship | 2022/01/08 14:00 | Castres v Stade Francais | W | 15-9 |
| French Rugby Championship | 2022/01/02 17:00 | Castres v La Rochelle | W | 31-30 |
| French Rugby Championship | 2021/12/26 17:00 | Perpignan v Castres | W | 19-20 |
| European Rugby Champions Cup | 2021/12/18 20:00 | Munster v Castres | L | 19-13 |
| European Rugby Champions Cup | 2021/12/12 17:30 | Castres v Harlequins | L | 18-20 |
| French Rugby Championship | 2021/12/04 14:00 | Castres v Racing Metro | W | 25-3 |
| French Rugby Championship | 2021/11/27 14:00 | Montpellier v Castres | L | 25-24 |