- Carrick
- Carson
- Caruthers
- Casa Conejo
- Castro Valley
- Castroville
- Cathedral City
- Cayucos
- Central Valley (historical)
- Caldor
- Cambridge Oaks
- Cameron Airpark Estates
- Camino Heights
- Camp Richardson
- Campana
- Cedar Grove
- Cedar Grove
- Claussenius
- Cold Springs
- Coyoteville
- Croft
- Channel Islands Beach
- Charter Oak
- Calflax
- Camp Sierra
- Cecile
- Cedar Crest
- Cedarbrook
- Cella
- Chaney Ranch