Home History
| UK Friendlies | 2021/07/17 13:00 | Cleethorpes Town v Grimsby | W | 1-4 |
| England League 2 | 2021/05/08 14:00 | Cambridge Utd v Grimsby | L | 3-0 |
| England League 2 | 2021/05/01 14:00 | Grimsby v Port Vale | W | 1-0 |
| England League 2 | 2021/04/27 18:00 | Exeter v Grimsby | L | 3-2 |
| England League 2 | 2021/04/24 14:00 | Oldham v Grimsby | W | 1-2 |
| England League 2 | 2021/04/20 18:00 | Grimsby v Morecambe | L | 0-3 |
| England League 2 | 2021/04/17 11:30 | Grimsby v Bolton | W | 2-1 |
| England League 2 | 2021/04/10 14:00 | Bradford v Grimsby | L | 1-0 |
Away History
| Club Friendly List | 2021/07/21 18:00 | Harrogate Town v Rotherham | W | 1-3 |
| Club Friendly List | 2021/07/20 18:00 | Rochdale v Rotherham | D | 2-2 |
| Europe Friendlies | 2021/07/10 12:00 | Parkgate v Rotherham | W | 0-11 |
| England Championship | 2021/05/08 11:30 | Cardiff v Rotherham | D | 1-1 |
| England Championship | 2021/05/04 18:15 | Luton v Rotherham | D | 0-0 |
| England Championship | 2021/05/01 14:00 | Rotherham v Blackburn | D | 1-1 |
| England Championship | 2021/04/27 18:00 | Brentford v Rotherham | L | 1-0 |
| England Championship | 2021/04/24 14:00 | Barnsley v Rotherham | L | 1-0 |