| 31 Aug 18 | Keston Davies |  Swansea CitySWA | → |  Notts CountyNOTT | Loan |
| 25 Aug 18 | C. Carter-Vickers Cameron Carter-Vickers |  Tottenham HotspurTOT | → | Swansea CitySWA | Loan |
| 25 Aug 18 | C. Carter-Vickers Cameron Carter-Vickers | Tottenham HotspurTOT | → | Swansea CitySWA | Loan |
| 09 Aug 18 | D. John Declan John |  RangersRAN | → | Swansea CitySWA | Undisclosed |
| 09 Aug 18 | J. Ayew Jordan Ayew | Swansea CitySWA | → |  Crystal PalaceCRY | Loan |
| 09 Aug 18 | D. John Declan John | RangersRAN | → | Swansea CitySWA | Undisclosed |
| 09 Aug 18 | F. Fernández Federico Fernández | Swansea CitySWA | → |  Newcastle UnitedNEW | Undisclosed |
| 09 Aug 18 | S. Clucas Sam Clucas | Swansea CitySWA | → |  Stoke CitySTK | Undisclosed |
| 09 Aug 18 | J. Ayew Jordan Ayew | Swansea CitySWA | → | Crystal PalaceCRY | Loan |
| 09 Aug 18 | J. Amat Jordi Amat | Swansea CitySWA | → |  Rayo VallecanoRAY | Undisclosed |
| 09 Aug 18 | J. Amat Jordi Amat | Swansea CitySWA | → | Rayo VallecanoRAY | Undisclosed |
| 09 Aug 18 | F. Fernández Federico Fernández | Swansea CitySWA | → | Newcastle UnitedNEW | Undisclosed |
| 02 Aug 18 | A. Mawson Alfie Mawson | Swansea CitySWA | → |  FulhamFUL | Undisclosed |
| 02 Aug 18 | A. Mawson Alfie Mawson | Swansea CitySWA | → | FulhamFUL | Undisclosed |
| 31 Jul 18 | B. McKay Barrie McKay |  Nottingham ForestFOR | → | Swansea CitySWA | Undisclosed |
| 31 Jul 18 | Bersant Celina |  Manchester CityMNC | → | Swansea CitySWA | Undisclosed |
| 31 Jul 18 | Bersant Celina | Manchester CityMNC | → | Swansea CitySWA | Undisclosed |
| 27 Jul 18 | A. Ayew André Ayew | Swansea CitySWA | → |  FenerbahceFEN | Loan |
| 16 Jul 18 | K. Bartley Kyle Bartley | Swansea CitySWA | → |  West Bromwich AlbionWBA | Undisclosed |
| 16 Jul 18 | B. Bastón Borja Bastón | Swansea CitySWA | → |  AlavésALV | Loan |
| 16 Jul 18 | B. Bastón Borja Bastón | Swansea CitySWA | → | AlavésALV | Loan |
| 14 Jul 18 | J. Asoro Joel Asoro |  SunderlandSUN | → | Swansea CitySWA | Undisclosed |
| 02 Jul 18 | A. King Adam King | Swansea CitySWA | → |  Peterborough UnitedPET | Loan |
| 01 Jul 18 | K. Sung-Yueng Ki Sung-Yueng | Swansea CitySWA | → | Newcastle UnitedNEW | Free |
| 01 Jul 18 | K. Sung-Yueng Ki Sung-Yueng | Swansea CitySWA | → | Newcastle UnitedNEW | Free |
| 01 Jul 18 | Yan Dhanda |  LiverpoolLIV | → | Swansea CitySWA | Free |
| 27 Jun 18 | R. Mesa Roque Mesa | Swansea CitySWA | → |  SevillaSEV | Undisclosed |
| 27 Jun 18 | R. Mesa Roque Mesa | Swansea CitySWA | → | SevillaSEV | Undisclosed |
| 31 Jan 18 | O. McBurnie Oliver McBurnie | Swansea CitySWA | → |  BarnsleyBAR | Loan |
| 31 Jan 18 | A. King Andy King |  Leicester CityLEI | → | Swansea CitySWA | Loan |
| 31 Jan 18 | Jack Withers | BUXBoston UnitedBoston United | → | Swansea CitySWA | Undisclosed |
| 31 Jan 18 | O. McBurnie Oliver McBurnie | Swansea CitySWA | → | BarnsleyBAR | Loan |
| 31 Jan 18 | A. Ayew André Ayew |  West Ham UnitedWHU | → | Swansea CitySWA | Undisclosed |
| 30 Jan 18 | J. Rodon Joe Rodon | Swansea CitySWA | → |  Cheltenham TownCHL | Loan |
| 30 Jan 18 | R. Mesa Roque Mesa | Swansea CitySWA | → | SevillaSEV | Loan |
| 30 Jan 18 | R. Mesa Roque Mesa | Swansea CitySWA | → | SevillaSEV | Loan |
| 29 Jan 18 | A. King Adam King | Swansea CitySWA | → |  Mansfield TownMAN | Loan |
| 25 Jan 18 | J. Fulton Jay Fulton | Swansea CitySWA | → |  Wigan AthleticWGA | Loan |