| 31 Aug 18 | C. Martin Chris Martin |  Derby CountyDER | → |  Hull CityHUL | Loan |
| 31 Aug 18 | C. Jerome Cameron Jerome | Derby CountyDER | → |  GoztepeGOZ | Undisclosed |
| 31 Aug 18 | T. Elsnik Timi Max Elsnik | Derby CountyDER | → |  Mansfield TownMAN | Loan |
| 31 Aug 18 | C. Guy Callum Guy | Derby CountyDER | → |  BlackpoolBLP | Loan |
| 28 Aug 18 | K. Gordon Kellan Gordon | Derby CountyDER | → |  Lincoln CityLCN | Loan |
| 16 Aug 18 | L. Thomas Luke Thomas | Derby CountyDER | → |  Coventry CityCOV | Loan |
| 15 Aug 18 | N. Blackman Nick Blackman | Derby CountyDER | → |  Sporting GijónRSG | Loan |
| 13 Aug 18 | J. Mitchell Jonathan Mitchell | Derby CountyDER | → |  Oxford UnitedOXF | Loan |
| 09 Aug 18 | J. Hanson Jamie Hanson | Derby CountyDER | → | Oxford UnitedOXF | Undisclosed |
| 09 Aug 18 | D. Holmes Duane Holmes |  Scunthorpe UnitedSCU | → | Derby CountyDER | Undisclosed |
| 08 Aug 18 | S. Malone Scott Malone |  Huddersfield TownHUD | → | Derby CountyDER | Undisclosed |
| 08 Aug 18 | S. Malone Scott Malone | Huddersfield TownHUD | → | Derby CountyDER | Undisclosed |
| 08 Aug 18 | M. Waghorn Martyn Waghorn |  Ipswich TownIPS | → | Derby CountyDER | Undisclosed |
| 07 Aug 18 | M. Vydra Matej Vydra | Derby CountyDER | → |  BurnleyBUR | Undisclosed |
| 07 Aug 18 | M. Vydra Matej Vydra | Derby CountyDER | → | BurnleyBUR | Undisclosed |
| 06 Aug 18 | F. Tomori Fikayo Tomori |  ChelseaCHE | → | Derby CountyDER | Loan |
| 06 Aug 18 | F. Tomori Fikayo Tomori | ChelseaCHE | → | Derby CountyDER | Loan |
| 02 Aug 18 | O. Zanzala Offrande Zanzala | Derby CountyDER | → |  Accrington StanleyACCR | Undisclosed |
| 31 Jul 18 | G. Evans George Evans |  ReadingREA | → | Derby CountyDER | Undisclosed |
| 26 Jul 18 | J. Marriott Jack Marriott |  Peterborough UnitedPET | → | Derby CountyDER | Undisclosed |
| 24 Jul 18 | C. Vernam Charles Vernam | Derby CountyDER | → |  Grimsby TownGRI | Undisclosed |
| 20 Jul 18 | F. Jozefzoon Florian Jozefzoon |  BrentfordBRE | → | Derby CountyDER | Undisclosed |
| 17 Jul 18 | H. Wilson Harry Wilson |  LiverpoolLIV | → | Derby CountyDER | Loan |
| 17 Jul 18 | M. Mount Mason Mount | ChelseaCHE | → | Derby CountyDER | Loan |
| 17 Jul 18 | H. Wilson Harry Wilson | LiverpoolLIV | → | Derby CountyDER | Loan |
| 17 Jul 18 | M. Mount Mason Mount | ChelseaCHE | → | Derby CountyDER | Loan |
| 03 Jul 18 | A. Weimann Andreas Weimann | Derby CountyDER | → |  Bristol CityBRC | Undisclosed |
| 31 Jan 18 | K. Palmer Kasey Palmer | ChelseaCHE | → | Derby CountyDER | Loan |
| 31 Jan 18 | K. Palmer Kasey Palmer | ChelseaCHE | → | Derby CountyDER | Loan |
| 31 Jan 18 | C. Martin Chris Martin | Derby CountyDER | → | ReadingREA | Loan |
| 31 Jan 18 | M. Bennett Mason Bennett | Derby CountyDER | → |  Notts CountyNOTT | Loan |
| 26 Jan 18 | D. Bent Darren Bent | Derby CountyDER | → |  Burton AlbionBRT | Loan |
| 25 Jan 18 | J. Shackell Jason Shackell | Derby CountyDER | → |  MillwallMIL | Loan |
| 16 Jan 18 | C. Jerome Cameron Jerome |  Norwich CityNOR | → | Derby CountyDER | Undisclosed |
| 12 Jan 18 | C. Guy Callum Guy | Derby CountyDER | → |  Bradford CityBRD | Loan |
| 11 Jan 18 | O. Zanzala Offrande Zanzala | Derby CountyDER | → | Accrington StanleyACCR | Loan |
| 08 Jan 18 | C. Vernam Charles Vernam | Derby CountyDER | → | Grimsby TownGRI | Loan |
| 05 Jan 18 | M. Lowe Max Lowe | Derby CountyDER | → |  Shrewsbury TownSHR | Loan |
| 04 Jan 18 | F. Rawson Farrend Rawson | Derby CountyDER | → |  Forest Green RoversFGR | Undisclosed |