| Name | Color | Sex | Year of birth | Microchip | Sire | Dam | Breed | Breeder |
|---|---|---|---|---|---|---|---|---|
| Symington | br. | c | 1893 | Ayrshire | Thoroughbred | Great Britain | ||
| Symmetry | grey | c | 1795 | Thoroughbred | Great Britain | |||
| Symmetry | bay | c | 1808 | Thoroughbred | Great Britain | |||
| Sympathetic Chord | grey | f | 1997 | Prospector's Music | Caveanella | Thoroughbred | USA | |
| Symphonie Pastor | f | 1981 | Thoroughbred | Italy | ||||
| Symphony West | d.-bay | f | 2025 | 900263000892117 | 1268-6 Secret West | Sekretnaya Missiya | Thoroughbred | Mrs Lapteva T.I. |
| Symphorosa | bay | f | 1926 | Light Brigade | Rose des Vents | Thoroughbred | USA | |
| Symra | bay | f | 2001 | 3641-1 Akvarium | 1585-3 Sigara | Thoroughbred | Abazinsky Farm | |
| Syn Gor | bay | c | 2016 | 643090000168565 | 1096-5 Sky Pride | 4245-6 Istora | Thoroughbred | Mr Geremeev V.S. |
| 1858-7 Syn Polka | bay | c | 2015 | 643090000215898 | 0919-5 Own Soup | 6337-8 Si Fo | Thoroughbred | Alokov A.A. |