Variant spellings are included, so there may be some duplication. If you know of something that should be included, please let me know
| Saggart |
| Saggart |
| Sarsfield |
| Scanell Fermoy, Co. Cork |
| Scot (archived) |
| Scott (archived) |
| Shackleton |
| Shanaghan Kilbaha, Moyvane (Newtownsandes), Co. Kerry |
| Shanahan Kilbaha, Moyvane (Newtownsandes), Co. Kerry |
| Shane (archived) |
| Shannahan Kilbaha, Moyvane (Newtownsandes), Co. Kerry |
| Shannan (archived) |
| Shannan |
| Shannon (archived) |
| Shannon |
| Shannuck |
| Sharry |
| Shay |
| Shay |
| Shea |
| Shea |
| Sheahan |
| Sheal |
| Sheales |
| Sheall |
| Sheals |
| Sheckleton |
| Shee |
| Shee |
| Sheehan |
| Sheehane |
| Shehan |
| Sheil |
| Sheilds |
| Sheill |
| Sheills |
| Sheils |
| Shekelton |
| Shekleton |
| Shennick |
| Shepard Durrow, Laois |
| Shephard Durrow, Laois |
| Shepherd Durrow, Laois |
| Sheppard Durrow, Laois |
| Shepperd Durrow, Laois |
| Sheradan |
| Sheradan |
| Sheridan |
| Sheridan |
| Sheriden |
| Sheriden |
| Sherridan |
| Sherridan |
| Sherrie |
| Sherry |
| Sherwood Westmeath/Newfoundland |
| Shiel |
| Shield |
| Shields |
| Shiell |
| Shiells |
| Shiels |
| Shinahane Kilbaha, Moyvane (Newtownsandes), Co. Kerry |
| Shine |
| Shinnick |
| Shinnock |
| Shirley |
| Sisk Cork |
| Smith Kilcornan, Co. Limerick |
| Smith Cavan |
| Smith Cavan |
| Smyth Kilcornan, Co. Limerick |
| Smyth Cavan |
| Smyth Cavan |
| Smythe Kilcornan, Co. Limerick |
| Smythe Cavan |
| Smythe Cavan |
| Solan |
| Solan |
| Solon |
| Solon |
| Spellan |
| Spellane |
| Spillane |
| Spillaun |
| Steen Monaghan/Canada |
| Steene Monaghan/Canada |
| Strangeman Mocollop, Co. Waterford |
| Strangman Mocollop, Co. Waterford |
| Strickland Sligo/Mayo |
| Strong |
| Stronge |
| Sulivan |
| Sulivan (archived) |
| Sulivan (archived) |
| Sulivan |
| Sulivan |
| Sulivan Macroom area, Co. Cork; and Glynn, Mourneabbey, Co. Cork |
| Sulivan |
| Sullivan |
| Sullivan (archived) |
| Sullivan (archived) |
| Sullivan |
| Sullivan |
| Sullivan Macroom area, Co. Cork; and Glynn, Mourneabbey, Co. Cork |
| Sullivan |
| Swanson |
| Swanston |
| Swanton |
| Sweeney |
| Sweeny |
| Sweny |
| Swiney |