Miasta Stany Zjednoczone, począwszy od litery O Strona 11
- Owen
- Ossineke
- Occoquan
- Oakland (Douglas County, Oregon)
- Old Field
- Onsted
- Odessa (Lincoln County, Washington)
- Old Fort
- Oscoda
- Oriental
- Oak Grove Heights
- Oshkosh (Garden County)
- Oak Creek (Routt County)
- Osceola (Polk County)
- Onaway
- Oakland (Coles County)
- Onamia
- Oreana
- Otisville (Genesee County)
- Olive Branch (Alexander County, Illinois)
- Orlinda
- Oak Level
- Oregon (Holt County, Missouri)
- Ossian (Winneshiek County)
- Orrick
- O'Donnell
- Orleans (Orleans County)
- Ogden (Champaign County)
- Oklahoma (Westmoreland County)
- Oxford (Johnson County, Iowa)
- Okoboji
- Old Washington
- Owensville (Clermont County)
- Orangeville (Stephenson County)
- Oakman
- Osmond
- Oklahoma (Clearfield County)
- Oppelo
- Oxford (Furnas County)
- Olympian Village
- Ojo Amarillo
- Oakley (Cassia County)
- Oakfield (Aroostook County)
- Old Forge (Herkimer County)
- Orient
- Oriskany Falls
- Osino
- Ohio City
- Onaga
- Oneida (Knox County, Illinois)