M
- (An Cabhán) Mullaghoran
- (County Monaghan) Mullabryan
- (County Donegal) Moyra
- (County Monaghan) Moy Bridge
- (An Cabhán) Mountnugent
- (An Cabhán) Mountain Lodge
- (County Donegal) Monasteraden
- (County Donegal) Mitchells Town
- (County Donegal) Milltown
- (County Monaghan) Milltown
- (County Monaghan) Mill Town
- (An Cabhán) Milltown
- (An Cabhán) Milltown
- (County Donegal) Meenasrona
- (County Donegal) Meenadeeny
- (County Donegal) Marble Hill
- (County Donegal) Malin More
- (County Donegal) Malin Beg
- (County Donegal) Maghery
- (County Donegal) Maghera
- (County Donegal) Maas Upper
- (County Donegal) Maas Lower
- (County Donegal) Maas
- (County Donegal) Milltown
- (County Donegal) Middletown
- (County Donegal) Meenaclady
- (County Donegal) Meenacung
- (County Donegal) Meendarragh
- (County Donegal) Millmount
- (County Donegal) Masiness