- Old Sparta
- Oak Crest
- Oak Park
- Ogburn Station
- Old Hollow Estates
- Old Town
- Oldtown
- Oak Ridge Park
- Osborne
- Oswego
- Oakland
- Oakton
- Oakhaven Farms
- Oregon Hill
- Ozark
- Orchard Hills
- Old Chapel Crossroads
- Orange
- Oak Hill
- Old Hundred
- Oak Ridge
- Oak Grove
- Oak Grove
- Oconaluftee Indian Village
- Oak Hill
- Oakland
- Oakdale
- Ormondsville
- Oak Grove
- Oak Hollow Lake