| Sincere | Man | American Names |
| Sincerity | Woman | American Names |
| Sissy | Woman | American Names |
| Skate | Unisex | American Names |
| Skip | Man | American Names |
| Skyanna | Woman | American Names |
| Skyla | Woman | American Names |
| Skylar | Unisex | American Names |
| Slash | Unisex | American Names |
| Slate | Man | American Names |
| Soctayvian | Man | American Names |
| Sojourner | Unisex | American Names |
| Sokka | Man | American Names |
| Sondra | Woman | American Names |
| Sonny | Man | American Names |
| Sontee | Unisex | American Names |
| Sookie | Woman | American Names |
| Sophilia | Woman | American Names |
| Sorina | Woman | American Names |
| Sosie | Woman | American Names |