| 02 Sept 19 | M. Lemina Mario Lemina |  SouthamptonSOU | → |  GalatasarayGAL | Loan |
| 02 Sept 19 | J. Hesketh Jake Hesketh | SouthamptonSOU | → |  Lincoln CityLCN | Loan |
| 02 Sept 19 | W. Hoedt Wesley Hoedt | SouthamptonSOU | → |  AntwerpANT | Loan |
| 01 Sept 19 | G. Carrillo Guido Carrillo | SouthamptonSOU | → |  LeganésLEG | Loan |
| 01 Sept 19 | G. Carrillo Guido Carrillo | SouthamptonSOU | → | LeganésLEG | Loan |
| 30 Aug 19 | M. Elyounoussi Mohammed Elyounoussi | SouthamptonSOU | → |  CelticCEL | Loan |
| 30 Aug 19 | M. Elyounoussi Mohammed Elyounoussi | SouthamptonSOU | → | CelticCEL | Loan |
| 29 Aug 19 | T. O'Connor Thomas O'Connor | SouthamptonSOU | → |  GillinghamGIL | Loan |
| 22 Aug 19 | F. Forster Fraser Forster | SouthamptonSOU | → | CelticCEL | Loan |
| 22 Aug 19 | F. Forster Fraser Forster | SouthamptonSOU | → | CelticCEL | Loan |
| 08 Aug 19 | K. Danso Kevin Danso |  FC AugsburgAUG | → | SouthamptonSOU | Loan |
| 08 Aug 19 | H. Reed Harrison Reed | SouthamptonSOU | → |  FulhamFUL | Loan |
| 08 Aug 19 | K. Danso Kevin Danso | FC AugsburgAUG | → | SouthamptonSOU | Undisclosed |
| 08 Aug 19 | H. Reed Harrison Reed | SouthamptonSOU | → | FulhamFUL | Loan |
| 08 Aug 19 | C. Austin Charlie Austin | SouthamptonSOU | → |  West Bromwich AlbionWBA | Undisclosed |
| 08 Aug 19 | C. Austin Charlie Austin | SouthamptonSOU | → | West Bromwich AlbionWBA | Undisclosed |
| 08 Aug 19 | K. Danso Kevin Danso | FC AugsburgAUG | → | SouthamptonSOU | Undisclosed |
| 08 Aug 19 | K. Danso Kevin Danso | FC AugsburgAUG | → | SouthamptonSOU | Loan |
| 07 Aug 19 | J. Sims Josh Sims | SouthamptonSOU | → |  New York Red BullsNY | Loan |
| 07 Aug 19 | J. Sims Josh Sims | SouthamptonSOU | → | New York Red BullsNY | Loan |
| 22 Jul 19 | J. Clasie Jordy Clasie | SouthamptonSOU | → |  AZ AlkmaarAZ | Undisclosed |
| 22 Jul 19 | J. Clasie Jordy Clasie | SouthamptonSOU | → | AZ AlkmaarAZ | Undisclosed |
| 13 Jul 19 | S. Gallagher Sam Gallagher | SouthamptonSOU | → |  Blackburn RoversBLK | Undisclosed |
| 13 Jul 19 | S. Gallagher Sam Gallagher | SouthamptonSOU | → | Blackburn RoversBLK | Undisclosed |
| 08 Jul 19 | J. Rose Jack Rose | SouthamptonSOU | → |  WalsallWAL | Loan |
| 02 Jul 19 | A. Jones Alfie Jones | SouthamptonSOU | → | GillinghamGIL | Loan |
| 01 Jul 19 | C. Adams Ché Adams |  Birmingham CityBIR | → | SouthamptonSOU | Undisclosed |
| 01 Jul 19 | M. Targett Matt Targett | SouthamptonSOU | → |  Aston VillaAVL | Undisclosed |
| 01 Jul 19 | M. Djenepo Moussa Djenepo |  Standard LiegeSTL | → | SouthamptonSOU | Undisclosed |
| 01 Jul 19 | D. Ings Danny Ings |  LiverpoolLIV | → | SouthamptonSOU | Undisclosed |
| 01 Jul 19 | S. Davis Steven Davis | SouthamptonSOU | → |  RangersRAN | Free |
| 01 Jul 19 | C. Adams Ché Adams | Birmingham CityBIR | → | SouthamptonSOU | Undisclosed |
| 01 Jul 19 | S. Davis Steven Davis | SouthamptonSOU | → | RangersRAN | Free |
| 26 Jan 19 | C. Soares Cédric Soares | SouthamptonSOU | → |  InternazionaleINT | Loan |
| 26 Jan 19 | C. Soares Cédric Soares | SouthamptonSOU | → | InternazionaleINT | Loan |
| 21 Jan 19 | W. Hoedt Wesley Hoedt | SouthamptonSOU | → |  Celta VigoCEL | Loan |
| 21 Jan 19 | W. Hoedt Wesley Hoedt | SouthamptonSOU | → | Celta VigoCEL | Loan |
| 11 Jan 19 | M. Gabbiadini Manolo Gabbiadini | SouthamptonSOU | → |  SampdoriaSAM | Undisclosed |
| 11 Jan 19 | M. Gabbiadini Manolo Gabbiadini | SouthamptonSOU | → | SampdoriaSAM | Undisclosed |