| Registered Name | Owner / Club | Status |
|---|---|---|
| Theseus R | Naomi Fisher Foxborough | Approved |
| Third Times A Charm | Cait Lynch Castledermot | Approved |
| Thisledome Pearl Mist | Joyce Morris Carrickmines | Approved |
| Thistletown Nordic Clover | Eleanor Wauchob Cill Dara | Approved |
| Thistletown Oldrock Cloe | Peter Dillon Killcarrick | Approved |
| Thistoshallpass (IRE) | Caroline Bellew Border Counties | Approved |
| Thomas | Graeme Power Waterford | Approved |
| Thomas Joseph | Nina Scott Slieve Bloom | Approved |
| Thomascourt Hula | Bernadette Flaherty Corrib | Approved |
| Thomastown Dolly | Ber Bourke Newpark | Approved |
| Thomastown Harold | Amy Murphy The Rower | Approved |
| Thomastown Lady Grey | Sarah Dollard Killcarrick | Approved |
| Thomond Lad | Terry Nolan Coole Lane | Approved |
| Thornbrook Coloured Maddy | Caitlin Steel South West | Approved |
| Thornbrook Ginger | Anthony Villar Ballycanew | Approved |