Gameplan
| Date | Round | Match | Match | Res. | Attendance | |
|---|---|---|---|---|---|---|
| 24.01.2021 |  | Matchday 13 | Real Unión - Leioa | REA - | 5:0 | |
| 07.02.2021 | | Matchday 15 | Real Unión - CD Laredo | REA - CDL | 4:1 | |
| 20.02.2021 | | Matchday 17 | Real Unión - Real Sociedad B | REA - RSO | 3:1 | |
| 27.02.2021 | | Matchday 18 | Real Unión - SD Amorebieta | REA - AMO | 2:0 | |
| 13.03.2021 | | Matchday 20 | Real Unión - Racing | REA - RAC | 0:2 | |
| 28.03.2021 | | Matchday 22 | Real Unión - Bilbao B | REA - Bil | 0:1 | |
| 07.04.2021 | | Matchday 1 | Real Unión - SD Tarazona | REA - TAR | 1:0 | |
| 18.04.2021 | | Matchday 3 | Real Unión - CD Ebro | REA - EBR | 3:0 | |
| 09.05.2021 | | Matchday 6 | Real Unión - Osasuna B | REA - | 0:1 | |
| 28.08.2021 |  | Matchday 1 | Real Unión - Inter de Madrid | REA - | 2:1 | |
| 10.09.2021 | | Matchday 3 | Real Unión - RC Celta B | REA - CEL | 1:4 | |
| 25.09.2021 | | Matchday 5 | Real Unión - CD Badajoz | REA - | 1:2 | |
| 09.10.2021 | | Matchday 7 | Real Unión - Deportivo | REA - DEP | 2:1 | |
| 31.10.2021 | | Matchday 10 | Real Unión - Racing | REA - RAC | 1:2 | |
| 13.11.2021 | | Matchday 12 | Real Unión - Unionistas | REA - | 1:1 | |
| 27.11.2021 | | Matchday 14 | Real Unión - Zamora | REA - Zam | 2:0 | |
| 11.12.2021 | | Matchday 16 | Real Unión - Racing Ferrol | REA - Fer | 0:3 |