Real Sociedad III (Segunda Division RFEF: Group 2): every transfer in and out, fees paid and earned, squad market value.
| Date | Player | From | To | Fee |
|---|---|---|---|---|
| 2025-09-01 | Ekain Díaz | Real Sociedad III | Rayo Cantabria | Free |
| 2025-08-13 | Aimar Olarra | Real Sociedad III | SD Logroñés | Free |
| 2025-07-18 | Iker Otadui | Real Sociedad III | UD Logroñés | Free |
| 2025-07-16 | Player | Real Sociedad III | Real Unión Club | Free |
| 2025-07-08 | Player | Real Sociedad III | SD Amorebieta | Free |
| 2025-07-01 | Gorka Carrera | Real Sociedad III | Real Sociedad | Free |
| 2025-07-01 | Gorka Gorosabel | Real Sociedad III | Real Sociedad | Free |
| 2025-07-01 | Lander Astiazaran | Real Sociedad III | Real Sociedad | Free |
| 2025-07-01 | Jakes Gorosabel | Real Sociedad | Real Sociedad III | Free |
| 2025-07-01 | Player | Real Sociedad III | TBC | Free |
| 2025-07-01 | Aimar Olarra | Real Sociedad III | TBC | Free |
| 2025-07-01 | Player | Real Sociedad III | TBC | Free |
| 2025-07-01 | Pablo Arenzana | Real Sociedad III | Villarreal CF | Free |
| 2024-07-17 | Player | Real Sociedad III | Recreativo Huelva | Loan |
| 2024-07-16 | Juan Carlos Pontones | Real Sociedad III | Granada II | Free |
| 2024-07-01 | Jakes Gorosabel | Real Sociedad III | Real Sociedad | Free |
| 2024-07-01 | Darío Ramírez | Real Sociedad III | Real Sociedad | Free |
| 2024-07-01 | Player | Real Sociedad III | Real Sociedad | Free |
| 2024-07-01 | Aitor Fraga | Real Sociedad III | Real Sociedad | Free |
| 2024-07-01 | Player | Real Sociedad III | Athletic Club II | Free |