O
- (Clay County) Oreana
- (Ashley County) Overton
- (Arkansas County) Ocala
- (Blount County) Old Camp
- (Coffee County) Olinghouse
- (Chilton County) Omco
- (Colbert County) Osceola
- (Ashley County) Overton Islands
- (Bibb County) Ola
- (Bibb County) Old Bullion
- (Bibb County) Oasis
- (Campbell County) Orovada
- (Bibb County) Osino
- (Bibb County) Owyhee