T
- (County Donegal) Tully More
- (County Monaghan) Tonyglassan
- (County Monaghan) Tullycarragh
- (County Monaghan) Tullychattina
- (County Monaghan) Tullyvin
- (County Monaghan) Thornford
- (County Monaghan) Tullanacrunat
- (County Monaghan) Tossy
- (County Monaghan) Tullynamalra Cross Roads
- (County Donegal) Tirraboy
- (County Donegal) Treantagh
- (County Donegal) Templemoyle
- (County Donegal) Three Trees
- (County Donegal) Tawny
- (County Donegal) Tawny
- (County Monaghan) Tydavnet
- (County Donegal) Teelin
- (County Donegal) Tievemore
- (County Monaghan) Tiragarvan
- (County Donegal) Termon
- (An Cabhán) Tober
- (County Donegal) Tonduff
- (County Donegal) Tormore Island
- (County Donegal) Tory Island
- (County Donegal) Treantagh
- (County Donegal) Tullybrook
- (County Donegal) Tullymore
- (County Monaghan) Tullynahinnera
- (An Cabhán) Tullyvin
- (County Donegal) Tully