California Neighborhoods O
- Oak Creek (13)
- Oak Grove (7)
- Oak Knoll (1)
- Oak Knoll-Redwood Park (8)
- Oak Park (1)
- Oak Park (8)
- Oak Valley Greens (5)
- Oak View (6)
- Oakmont Village (5)
- Oakridge (3)
- Ocean Crest (19)
- Ocean Hills (8)
- Ocean Park (81)
- Oceana (6)
- Ohlone (2)
- Oildale (7)
- Old Agoura (2)
- Old Davis North (1)
- Old East Davis (2)
- Old Las Palmas (3)
- Old Los Altos (1)
- Old North Sacramento (9)
- Old Oakland (4)
- Old Palo Alto (1)
- Old Sacramento (7)
- Old San Leandro (23)
- Old Town (5)
- Old Town (6)
- Old Town Kern (2)
- Olde Torrance Neighborhood (13)
- Oleander/Sunset (24)
- Olive Drive (2)
- Olive Drive Area (3)
- Olive Heights (2)
- Olivenhain (1)
- Olympia (3)
- Olympus Pointe (1)
- Orange Heights (1)
- Orange Park (1)
- Orangecrest (9)
- Orchard Hills (21)
- Ord Grove (1)
- Ortega Park (4)
- Ortega/SE Stockton (1)
- Oster (1)
- Otay Mesa (9)
- Otay Mesa West (13)
- Otay Ranch (78)
- Otay Ranch Village (12)
- Otay Town (7)
- Outer Mission (8)
- Outer Monterey (14)
- Outer Sunset (7)
- Overfelt (1)
- Oxnard Dunes (2)
- Oxnard Shores (24)