| Name | Color | Sex | Year of birth | Microchip | Sire | Dam | Breed | Breeder |
|---|---|---|---|---|---|---|---|---|
| Sylvie | bay | f | 1891 | Thoroughbred | France | |||
| Sylyk | chestnut | c | 1972 | 3084 Lugansk | 3500 Svirel | Thoroughbred | Issyk-Kul Stud | |
| 4831-6 Symbol of Success | bay | f | 2012 | Afleet Alex | Proud Angel | Thoroughbred | USA | |
| Symbolic Gesture | d.-bay | f | 2013 | Bernardini | Sweet Life | Thoroughbred | USA | |
| Symbolical | br. | f | 1908 | Symington | Revolver | Thoroughbred | Great Britain | |
| Symbolically | bay | f | 1983 | Flying Paster | Hail to the Queen | Thoroughbred | USA | |
| 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 |