| Name | Color | Sex | Year of birth | Microchip | Sire | Dam | Breed | Breeder |
|---|---|---|---|---|---|---|---|---|
| Three Up | bay | f | 1961 | Decathlon | Cequillo | Thoroughbred | USA | |
| Three Weeks | chestnut | f | 1946 | Big Game | Eleanor Cross | Thoroughbred | Great Britain | |
| Thriff | chestnut | f | 1865 | Stockwell | Braxey | Thoroughbred | Great Britain | |
| Throttle Wide | br. | f | 1936 | Flying Heels | Let Her Fly | Thoroughbred | USA | |
| Thrush | chestnut | f | 1837 | Object | Thoroughbred | USA | ||
| Thunder | bay | f | 1952 | Hyperion | Chenille | Thoroughbred | Great Britain | |
| Thunder Achiever | chestnut | f | 1993 | Thunder Puddles | Anthenian Girl | Thoroughbred | USA | |
| Thunder Bayou | chestnut | f | 2003 | Thunder Gulch | Bayou Storm | Thoroughbred | USA | |
| Thunder Bertie | chestnut | f | 1998 | Thunder Gulch | Alltheway Bertie | Thoroughbred | USA | |
| Thunder Blues | bay | f | 1993 | Cure The Blues | Dedicated Queen | Thoroughbred | USA |