California Neighborhoods O
- Oak Creek (17)
- Oak Grove (2)
- Oak Knoll (1)
- Oak Knoll Golf Links (1)
- Oak Knoll-Redwood Park (8)
- Oak Park (10)
- Oak Park (3)
- Oak Valley Greens (5)
- Oak View (18)
- Oakmont Village (3)
- Oakridge (6)
- Ocean Crest (8)
- Ocean Hills (8)
- Ocean Park (82)
- Oceana (4)
- Oceanview (1)
- Ohlone (2)
- Oildale (6)
- Old Davis North (2)
- Old East Davis (3)
- Old Lakewood City (2)
- Old Las Palmas (2)
- Old Los Altos (1)
- Old North Sacramento (3)
- Old Oakland (4)
- Old Palo Alto (2)
- Old Sacramento (6)
- Old San Leandro (23)
- Old Town (2)
- Old Town (7)
- Old Town Kern (2)
- Old West Sacramento (5)
- Olde Torrance Neighborhood (19)
- Oleander/Sunset (18)
- Olive Drive (2)
- Olive Drive Area (2)
- Olive Heights (6)
- Olivenhain (1)
- Olympia (3)
- Olympus Pointe (4)
- Orange Heights (1)
- Orange Park (2)
- Orangecrest (4)
- Orchard Hills (13)
- Orchard Park (1)
- Orinda View (1)
- Ortega Park (5)
- Otay Mesa (8)
- Otay Mesa West (14)
- Otay Ranch (82)
- Otay Ranch Village (10)
- Otay Town (7)
- Outer Mission (6)
- Outer Monterey (14)
- Outer Sunset (7)
- Oxnard Shores (16)