S
- (Mayo County) Stony Island
- (Mayo County) Saint’s Island
- (Mayo County) Shanvallyhugh
- (Mayo County) Struaun
- (Mayo County) Sheean
- (Mayo County) Slinaun
- (Mayo County) Shanvoley
- (Mayo County) Stonepark
- (Mayo County) Shandrum
- (Mayo County) Slaugar
- (Mayo County) Streamstown
- (Mayo County) Sranalee
- (Mayo County) Sallagher
- (Mayo County) Snugborough
- (Mayo County) Shanwar
- (Mayo County) Shanvallybeg
- (Mayo County) Sraheen
- (Mayo County) Stonehall
- (Mayo County) Srah
- (Mayo County) Sheeans
- (Mayo County) Skerdagh Lower
- (Mayo County) Srahmore
- (Mayo County) Srahrevagh
- (Mayo County) Shinnagh
- (Mayo County) Slinaunroe
- (Mayo County) Sixpenny Island
- (Mayo County) Smuttanagh
- (Mayo County) Shanrawy
- (Mayo County) Skiddernagh
- (County Galway) Sruthán