Southampton U21: every transfer in and out, fees paid and earned, squad market value, €5.5m spent and €6.3m earned.
| Date | Player | From | To | Fee |
|---|---|---|---|---|
| 2026-02-02 | Romeo Akachukwu | Southampton U21 | Colchester Utd. | Loan |
| 2026-02-02 | Daouda Traoré | Southampton U21 | Bari | Loan |
| 2025-09-29 | Victor Udoh | Southampton U21 | C. Budejovice | Free |
| 2025-08-16 | Rory Whittaker | Hibernian B | Southampton U21 | — |
| 2025-08-14 | Daouda Traoré | Southampton U21 | Betis Deportivo | Loan |
| 2025-07-01 | Jay Robinson | Southampton U21 | Southampton | — |
| 2025-02-03 | Victor Udoh | Royal Antwerp | Southampton U21 | — |
| 2025-02-03 | Joe O'Brien-Whitmarsh | Southampton U21 | Accrington | Loan |
| 2025-02-03 | Furkan Malak | Göztepe | Southampton U21 | Loan |
| 2024-08-31 | Rory MacLeod | Dundee United | Southampton U21 | Loan |
| 2024-08-31 | Daouda Traoré | Southampton U21 | Valenciennes FC | Loan |
| 2024-08-30 | Noel Buck | New England | Southampton U21 | Loan |
| 2024-08-30 | Jayden Meghoma | Southampton U21 | Brentford | €5.9m |
| 2024-08-30 | Daouda Traoré | OGC Nice B | Southampton U21 | €700k |
| 2024-08-05 | Romeo Akachukwu | Waterford FC | Southampton U21 | €375k |
| 2024-07-01 | Tyler Dibling | Southampton U21 | Southampton | — |
| 2024-07-01 | Jayden Moore | Southampton U18 | Southampton U21 | — |
| 2024-07-01 | Jay Robinson | Southampton U18 | Southampton U21 | — |
| 2024-02-01 | Thierry Small | Southampton U21 | Charlton | Free |
| 2024-01-12 | Joe O'Brien-Whitmarsh | Cork City | Southampton U21 | — |