T
- (County Leitrim) Treannadullagh
- (County Leitrim) Tullynamuckduff
- (Sligo) Treanmore
- (County Leitrim) Tullyrossmearan
- (County Galway) Twomileditch
- (County Galway) Turbot Island
- (County Leitrim) Tullynascreen
- (County Leitrim) Tullymurray
- (County Galway) Tully
- (County Galway) Tubber
- (Mayo County) The Triangle
- (Mayo County) Toormore
- (County Galway) Tooreeny
- (Mayo County) Tooreen
- (County Galway) Tooravoola
- (County Galway) Toomard
- (Sligo) Toberscanavan
- (Roscommon) Toberdan
- (County Galway) Tirneevin
- (Roscommon) Tinny Park
- (County Galway) Tiaquin
- (Roscommon) Thomas Street
- (Mayo County) Termoncarragh
- (Roscommon) Tarmonbarry
- (Sligo) Templeboy
- (Mayo County) Tawnyinah
- (County Galway) Tawin Island
- (Mayo County) Tullaghanbaun
- (Mayo County) Tomboholla
- (Mayo County) Tawnaghbeg