| Name | Color | Sex | Year of birth | Microchip | Sire | Dam | Breed | Breeder |
|---|---|---|---|---|---|---|---|---|
| Thorn Flower | bay | f | 2007 | Montjeu | Champagne Cocktail | Thoroughbred | Canada | |
| Thorn Wood | bay | f | 1942 | Bois Roussel | Thoroughbred | Great Britain | ||
| Thoroly Blue | bay | f | 1967 | Blue Prince | Ambwithor | Thoroughbred | USA | |
| Thorough Fair | bay | f | 1993 | Quiet American | Very Fair | Thoroughbred | USA | |
| 1279-6 Thought I Forgot | bay | c | 2009 | 643094100120772 | Lemon Drop Kid | Captured Moment | Thoroughbred | USA |
| Thoughtless | f | 1875 | Thoroughbred | |||||
| Thoughtless Beauty | chestnut | f | 1918 | Disguise | Coquette | Thoroughbred | USA | |
| Thousand Words | bay | c | 2004 | Dansili | Verbose | Thoroughbred | Great Britain | |
| Thousand Words | bay | c | 2017 | Pioneerof the Nile | Pomeroys Pistol | Thoroughbred | USA | |
| Thread | bay | f | 1991 | Topsider | Knot | Thoroughbred | USA |