Miasta Stany Zjednoczone, począwszy od litery O Strona 13
- O'Brien
- Odum
- Oxford Junction
- Oak Ridge (Kaufman County)
- Ocheyedan
- Oglesby (Coryell County)
- Oak Park (Emanuel County)
- Otis (Washington County)
- Onyx
- Otterville
- Oacoma
- Offerman
- Osyka
- Oklee
- Orland (Steuben County)
- Otwell
- Orbisonia
- Olivet (Vermilion County)
- Ochelata
- Osborn
- Oakesdale
- Oretta
- Orchid
- Orestes
- Onekama
- Oneida (Clay County, Kentucky)
- Orient (Adair County, Iowa)
- Owensburg
- Oliver (Douglas County, Wisconsin)
- Osmond (Lincoln County, Wyoming)
- Oak Grove (Rock Island County)
- Orcas
- Oktaha
- Otter Lake
- Orleans (Harlan County, Nebraska)
- Orchard
- Oakview
- Ogilvie
- Oak Valley (Navarro County)
- Odessa (New Castle County)
- Oden
- Oak Island (Chambers County)
- Oceanside (Tillamook County)
- Oval
- Orient (Franklin County, Illinois)
- Orick
- Optima
- Ocean Breeze Park
- Oilton (Webb County)
- Old Brownsboro Place