- Churchtown
- Cincinnati
- Circle Green
- Circle Hill
- Circle Hills
- Circle Island
- Circle View Acres
- Circle Z Mobile Home Park
- Circleville
- Circlewood
- City View Heights
- Claiborne
- Claiborne East
- Claiborne West
- Clare
- Claremont
- Claridon
- Claridon
- Clarington
- Clarion
- Clark
- Clark
- Clark Corners
- Clark-Fulton
- Clark Island
- Clarks
- Clarksburg
- Clarksfield
- Clarkson
- Clarksville