| 01 Sept 15 | B. Johnson Bradley Johnson |  Norwich CityNOR | → |  Derby CountyDER | Undisclosed |
| 01 Sept 15 | J. Butterfield Jacob Butterfield |  Huddersfield TownHUD | → | Derby CountyDER | Undisclosed |
| 01 Sept 15 | B. Johnson Bradley Johnson | Norwich CityNOR | → | Derby CountyDER | Undisclosed |
| 29 Jul 15 | K. Thomas Kwame Thomas | Derby CountyDER | → |  BlackpoolBLP | Loan |
| 25 Jul 15 | C. Sammon Conor Sammon | Derby CountyDER | → |  Sheffield UnitedSHU | Loan |
| 23 Jul 15 | J. Shackell Jason Shackell |  BurnleyBUR | → | Derby CountyDER | Undisclosed |
| 21 Jul 15 | R. Albentosa Raúl Albentosa | Derby CountyDER | → |  MálagaMCF | Loan |
| 21 Jul 15 | R. Albentosa Raúl Albentosa | Derby CountyDER | → | MálagaMCF | Loan |
| 15 Jul 15 | F. Rawson Farend Rawson | Derby CountyDER | → |  Rotherham UnitedROT | Loan |
| 15 Jul 15 | K. Roos Kelle Roos | Derby CountyDER | → | Rotherham UnitedROT | Loan |
| 03 Jul 15 | T. Ince Tom Ince |  Hull CityHUL | → | Derby CountyDER | Undisclosed |
| 02 Jul 15 | J. Ward Jamie Ward | Derby CountyDER | → |  Nottingham ForestFOR | Free |
| 01 Jul 15 | A. Pearce Alex Pearce |  ReadingREA | → | Derby CountyDER | Free |
| 01 Jul 15 | C. Baird Chris Baird |  West Bromwich AlbionWBA | → | Derby CountyDER | Free |
| 01 Jul 15 | D. Bent Darren Bent |  Aston VillaAVL | → | Derby CountyDER | Free |
| 01 Jul 15 | C. Baird Chris Baird | West Bromwich AlbionWBA | → | Derby CountyDER | Free |
| 01 Jul 15 | D. Bent Darren Bent | Aston VillaAVL | → | Derby CountyDER | Free |
| 18 Jun 15 | A. Weimann Andreas Weimann | Aston VillaAVL | → | Derby CountyDER | Undisclosed |
| 18 Jun 15 | A. Weimann Andreas Weimann | Aston VillaAVL | → | Derby CountyDER | Undisclosed |
| 12 Jun 15 | S. Carson Scott Carson |  Wigan AthleticWGA | → | Derby CountyDER | Free |
| 26 Mar 15 | S. McDonald Shaquille McDonald | Derby CountyDER | → |  Cheltenham TownCHL | Loan |
| 13 Mar 15 | R. Sharpe Rhys Sharpe | Derby CountyDER | → |  Shrewsbury TownSHR | Loan |
| 07 Mar 15 | F. Rawson Farend Rawson | Derby CountyDER | → | Rotherham UnitedROT | Loan |
| 02 Feb 15 | J. Lingard Jesse Lingard |  Manchester UnitedMAN | → | Derby CountyDER | Loan |
| 02 Feb 15 | T. Ince Tom Ince | Hull CityHUL | → | Derby CountyDER | Loan |
| 02 Feb 15 | J. Lingard Jesse Lingard | Manchester UnitedMAN | → | Derby CountyDER | Loan |
| 02 Feb 15 | I. Calero Ivan Calero | Derby CountyDER | → |  Burton AlbionBRT | Loan |
| 02 Feb 15 | T. Ince Tom Ince | Hull CityHUL | → | Derby CountyDER | Loan |
| 30 Jan 15 | T. Naylor Tom Naylor | Derby CountyDER | → | Burton AlbionBRT | Loan |
| 23 Jan 15 | P. Coutts Paul Coutts | Derby CountyDER | → | Sheffield UnitedSHU | Undisclosed |
| 23 Jan 15 | K. Freeman Kieran Freeman | Derby CountyDER | → | Sheffield UnitedSHU | Free |
| 16 Jan 15 | R. Albentosa Raúl Albentosa |  EibarEIB | → | Derby CountyDER | Undisclosed |
| 16 Jan 15 | R. Albentosa Raúl Albentosa | EibarEIB | → | Derby CountyDER | Undisclosed |
| 15 Jan 15 | C. Sammon Conor Sammon | Derby CountyDER | → | Rotherham UnitedROT | Loan |
| 15 Jan 15 | S. Warnock Stephen Warnock |  Leeds UnitedLEE | → | Derby CountyDER | Undisclosed |
| 09 Jan 15 | A. Santos Alfie Santos | Derby CountyDER | → |  Notts CountyNOTT | Loan |
| 08 Jan 15 | A. Santos Alfie Santos | Derby CountyDER | → | Notts CountyNOTT | Loan |
| 03 Jan 15 | D. Bent Darren Bent | Aston VillaAVL | → | Derby CountyDER | Loan |
| 03 Jan 15 | D. Bent Darren Bent | Aston VillaAVL | → | Derby CountyDER | Loan |
| 01 Jan 15 | R. Shotton Ryan Shotton |  Stoke CitySTK | → | Derby CountyDER | Undisclosed |
| 01 Jan 15 | R. Shotton Ryan Shotton | Stoke CitySTK | → | Derby CountyDER | Undisclosed |