- Cascade Mobile Villa
- Cascade Park East
- Cascade Park West
- Cascade Valley
- Cascade Vista Mobile Estates
- Cascades Island
- Casey Island
- Cashmere
- Cashup
- Casino Corner
- Castle Island
- Castle Rock
- Cat Island
- Caterpillar Island
- Cathan
- Cathcart
- Cathlamet
- Cavalero Corner
- Cayou Island
- Cedar Crest Mobile Home Park
- Cedar Crossing
- Cedar Falls
- Cedar Glen Mobile Home Park
- Cedar Glen Mobile Home Park
- Cedar Grove
- Cedar Grove Mobile Home Park
- Cedar Hills Mobile Home Park
- Cedar Lane Mobile Estates
- Cedar Lane Mobile Home Park
- Cedar Mountain