| Name ▲ | Age | Gender | Owner | Actions |
|---|
| Irish Cat | 1 | Colt | Hidden Oak Farm | |
| Irish Colors | 1 | Filly | Tall Oaks Farm | |
| Iron Head | 1 | Colt | Gintara Lodge | |
| Iron Maiden | 1 | Filly | Dreadnought | |
| Island In The Sky | 1 | Colt | Generous Bloodstock | |
| Isle of Bright | 1 | Filly | Sakura Springs | |
| Isola di Loretto | 1 | Filly | Generous Bloodstock | |
| Isère | 1 | Colt | Generous Bloodstock | |
| Ita Ti Ina | 1 | Colt | Hidden Oak Farm | |
| Italian Finale | 1 | Filly | Gintara Lodge | |
| Italian Passion | 1 | Colt | Gintara Lodge | |
| Ithildin | 1 | Filly | Fair Isle Farm | |
| Itzcalli | 1 | Filly | Clicker Lab | |
| Jabberwocky | 1 | Colt | New Boston Stables | |
| Jamaica | 1 | Colt | Dreadnought | |
| Javascript | 1 | Colt | New Boston Stables | |
| Jet Set Model | 1 | Filly | Tall Oaks Farm | |
| Jiminy Cricket | 1 | Colt | Gotapa Racing | |
| Jimmy Anderson | 1 | Colt | Dreadnought | |
| Judas Priest | 1 | Colt | Dreadnought | |