Head to Head
| England Development League 2 | 2025/02/07 13:30 | Millwall U21 v Cardiff U21 | L | 2-0 |
| England Development League 2 | 2023/12/18 13:30 | Millwall U21 v Cardiff U21 | L | 5-1 |
| England Development League 2 | 2023/09/26 13:00 | Cardiff U21 v Millwall U21 | L | 0-1 |
| England Development League 2 | 2023/02/21 12:00 | Cardiff U21 v Millwall U21 | W | 4-2 |
| England Development League 2 | 2022/10/31 14:00 | Millwall U21 v Cardiff U21 | L | 5-0 |
Home History
| England Development League 2 | 2025/02/07 13:30 | Millwall U21 v Cardiff U21 | L | 2-0 |
| England U21 Premier League Cup | 2025/02/01 12:00 | Cardiff U21 v Everton U21 | W | 3-2 |
| England Development League 2 | 2025/01/24 13:00 | Charlton U21 v Cardiff U21 | L | 6-1 |
| England Development League 2 | 2025/01/14 14:00 | Cardiff U21 v Brentford U21 | L | 0-3 |
| England Development League 2 | 2025/01/07 13:00 | Ipswich U21 v Cardiff U21 | L | 5-1 |
| England U21 Premier League Cup | 2024/12/19 19:00 | Cardiff U21 v Watford U21 | W | 3-1 |
| England Development League 2 | 2024/12/16 14:00 | Cardiff U21 v QPR U21 | W | 2-1 |
| England Development League 2 | 2024/12/06 19:00 | Colchester U21 v Cardiff U21 | W | 0-1 |
Away History
| England Development League 2 | 2025/02/07 13:30 | Millwall U21 v Cardiff U21 | W | 2-0 |
| England Development League 2 | 2025/02/04 14:00 | Millwall U21 v Bournemouth U21 | W | 2-0 |
| England Development League 2 | 2025/01/24 14:00 | Millwall U21 v Swansea U21 | W | 5-0 |
| England Development League 2 | 2025/01/20 13:00 | Swansea U21 v Millwall U21 | W | 3-4 |
| England Development League 2 | 2025/01/07 19:00 | QPR U21 v Millwall U21 | W | 0-2 |
| England Development League 2 | 2024/12/10 13:30 | Millwall U21 v Ipswich U21 | W | 3-0 |
| England Development League 2 | 2024/12/02 13:00 | Watford U21 v Millwall U21 | W | 1-3 |
| England Development League 2 | 2024/11/14 12:00 | Millwall U21 v Sheffield Wed U21 | D | 1-1 |