| Shoney | Unisex | Irish Names |
| Sile | Woman | Irish Names |
| Sinead | Woman | Irish Names |
| Siobhan | Woman | Irish Names |
| Síofra | Woman | Irish Names |
| Sionn | Man | Irish Names |
| Siusan | Woman | Irish Names |
| Slaine | Unisex | Irish Names |
| Sloan | Man | Irish Names |
| Slone | Man | Irish Names |
| Sonnagh | Unisex | Irish Names |
| Sorcha | Woman | Irish Names |
| Suibhne | Man | Irish Names |
| Sullivan | Man | Irish Names |
| Tadhg | Man | Irish Names |
| Taisce | Unisex | Irish Names |
| Tara | Woman | Irish Names |
| Tarmon | Man | Irish Names |
| Tavish | Man | Irish Names |
| Teagan | Unisex | Irish Names |