Towns
| State | City/Town | Town Title |
|---|---|---|
| California | Orange | Orange, CA |
| California | Orange Cove | Orange Cove, CA |
| California | Orangevale | Orangevale, CA |
| California | Oregon House | Oregon House, CA |
| California | Orick | Orick, CA |
| California | Orinda | Orinda, CA |
| California | Orland | Orland, CA |
| California | Orleans | Orleans, CA |
| California | Oro Grande | Oro Grande, CA |
| California | Orosi | Orosi, CA |
| California | Oroville | Oroville, CA |
| California | Oxnard | Oxnard, CA |
| California | Pacific Grove | Pacific Grove, CA |
| California | Pacific Palisades | Pacific Palisades, CA |
| California | Pacifica | Pacifica, CA |
| California | Pacoima | Pacoima, CA |
| California | Paicines | Paicines, CA |
| California | Pala | Pala, CA |
| California | Palermo | Palermo, CA |
| California | Palm Desert | Palm Desert, CA |
| California | Palm Springs | Palm Springs, CA |
| California | Palmdale | Palmdale, CA |
| California | Palo Alto | Palo Alto, CA |
| California | Palo Cedro | Palo Cedro, CA |
| California | Palo Verde | Palo Verde, CA |