| MD | Players | Club | Nationality | DOB | A(D) |
|---|---|---|---|---|---|
| 14-Oct-2017 |  Marcus Smith | Harlequins | England | 14-Feb-1999 | 18(243) |
| 14-Oct-2017 |  Thomas Darmon | Montpellier | France | 12-May-1998 | 19(155) |
| 15-Oct-2017 |  Nicholas Isiekwe | Saracens | England | 20-Apr-1998 | 19(178) |
| 14-Jan-2018 | Matt Fagerson | Glasgow Warriors | Scotland | 16-Jul-1998 | 19(182) |
| 15-Oct-2017 | Keelan Giles | Ospreys | Wales | 29-Jan-1998 | 19(259) |
| 13-Jan-2018 | Gele Aprasidze | Montpellier | Georgia | 14-Jan-1998 | 19(364) |
| 14-Jan-2018 | Marco Riccioni | Benetton Treviso | Italy | 19-Oct-1997 | 20(87) |
| 10-Dec-2017 | Pierre Bourgarit | La Rochelle | France | 12-Sep-1997 | 20(89) |
| 14-Oct-2017 | Zac Mercer | Bath | England | 28-Jun-1997 | 20(108) |
| 15-Dec-2017 | Archie White | Harlequins | England | 05-Aug-1997 | 20(132) |
| 14-Jan-2018 |  Jordan Larmour | Leinster | Ireland | 10-Jun-1997 | 20(218) |
| 30-Mar-2018 | Arthur Retiere | La Rochelle | France | 01-Aug-1997 | 20(241) |
| 16-Dec-2017 | Gabriel Ngandebe | Montpellier | France | 30-Mar-1997 | 20(261) |
| 14-Jan-2018 |  William Evans | Leicester Tigers | England | 28-Jan-1997 | 20(351) |
| 15-Oct-2017 |  Josh Macleod | Scarlets | Wales | 27-Oct-1996 | 20(353) |
| 15-Oct-2017 | Owen Watkin | Ospreys | Wales | 12-Oct-1996 | 21(3) |
| 08-Dec-2017 | Scott Cummings | Glasgow Warriors | Scotland | 03-Dec-1996 | 21(5) |
| 14-Oct-2017 | Max Clarke | Bath | England | 03-Oct-1996 | 21(11) |
| 15-Oct-2017 |  Damian Penaud | Clermont Auvergne | France | 25-Sep-1996 | 21(20) |
| 21-Jan-2018 |  Jack Willis | London Wasps | England | 24-Dec-1996 | 21(28) |
| 08-Dec-2017 | Matthew Smith | Glasgow Warriors | Scotland | 05-Oct-1996 | 21(64) |
| 14-Oct-2017 | James Ryan | Leinster | Ireland | 24-Jul-1996 | 21(82) |
| 14-Oct-2017 | Sam Underhill | Bath | England | 22-Jul-1996 | 21(84) |
| 21-Oct-2017 | Anthony Jelonch | Castres | France | 28-Jul-1996 | 21(85) |
| 14-Oct-2017 | Joe Marchant | Harlequins | England | 16-Jul-1996 | 21(90) |
| 14-Jan-2018 | George Worth | Leicester Tigers | England | 08-Oct-1996 | 21(98) |
| 21-Oct-2017 |  Harry Mallinder | Northampton Saints | England | 13-Jun-1996 | 21(130) |
| 15-Dec-2017 | Lewis Boyce | Harlequins | England | 30-Jul-1996 | 21(138) |
| 14-Jan-2018 | Charlie Thacker | Leicester Tigers | England | 10-Aug-1996 | 21(157) |
| 15-Oct-2017 | Judicael Cancoriet | Clermont Auvergne | France | 25-Apr-1996 | 21(173) |
| 15-Oct-2017 | Anthony Belleau | Toulon | France | 08-Apr-1996 | 21(190) |
| 13-Oct-2017 |  Jacob Stockdale | Ulster | Ireland | 03-Apr-1996 | 21(193) |
| 21-Oct-2017 | Rudy Gahetau | Toulon | France | 08-Apr-1996 | 21(196) |
| 13-Jan-2018 | Mathieu Tanguy | La Rochelle | France | 05-Jun-1996 | 21(222) |
| 09-Dec-2017 |  Sam Arnold | Munster | Ireland | 08-Apr-1996 | 21(245) |
| 14-Oct-2017 | Luca Sperandio | Benetton Treviso | Italy | 28-Jan-1996 | 21(260) |
| 14-Oct-2017 | Zander Fagerson | Glasgow Warriors | Scotland | 19-Jan-1996 | 21(269) |
| 21-Oct-2017 | Adam Beard | Ospreys | Wales | 07-Jan-1996 | 21(288) |
| 21-Oct-2017 | Camille Chat | Racing CF | France | 18-Dec-1995 | 21(308) |
| 09-Dec-2017 | Boris Palu | Racing CF | France | 04-Feb-1996 | 21(309) |
| 10-Dec-2017 | Elia Elia | Harlequins | Samoa | 22-Jan-1996 | 21(323) |
| 13-Oct-2017 | Kieran Treadwell | Ulster | England | 16-Nov-1995 | 21(332) |
| 16-Dec-2017 | Daniel Jones | Scarlets | Wales | 07-Jan-1996 | 21(344) |
| 14-Oct-2017 | Joey Carbery | Leinster | Ireland | 01-Nov-1995 | 21(348) |
| 09-Dec-2017 | Lewis Ludlam | Northampton Saints | England | 08-Dec-1995 | 22(2) |
| 21-Oct-2017 | Louis Dupichat | Racing CF | France | 23-Sep-1995 | 22(29) |
| 15-Oct-2017 | David Ribbans | Northampton Saints | England | 29-Aug-1995 | 22(48) |
| 14-Oct-2017 | Marco Lazzaroni | Benetton Treviso | Italy | 18-Aug-1995 | 22(58) |
| 10-Dec-2017 | Thomas Jolmes | La Rochelle | France | 08-Oct-1995 | 22(64) |
| 14-Oct-2017 | Charlie Ewels | Bath | England | 29-Jun-1995 | 22(108) |
MD = Match date,
DOB = Date of birth,
A(D) = Age(days).