C
- (Sitka City and Borough) Cannon Island
- (Yakutat City and Borough) Canoe Island
- (Juneau City and Borough) Canyon Island
- (Prince of Wales-Hyder Census Area) Cap Island
- (Ketchikan Gateway Borough) Carlanna
- (Prince of Wales-Hyder Census Area) Caracol Island
- (Thomas County) Carlton Island
- (Ketchikan Gateway Borough) Carp Island
- (Perry County) Carroll Island
- (Madison County) Castle Islands
- (Ketchikan Gateway Borough) Cat Island
- (Prince of Wales-Hyder Census Area) Cat Island
- (Prince of Wales-Hyder Census Area) Catalina Island
- (Sitka City and Borough) Caution Island
- (Sitka City and Borough) Catherine Island
- (Madison County) Cedar Island
- (Perry County) Cedar Island
- (Prince of Wales-Hyder Census Area) Center Island
- (Thomas County) Center Island
- (Ketchikan Gateway Borough) Center Islets
- (Sitka City and Borough) Chaichei Islands
- (Prince of Wales-Hyder Census Area) Coronados Islands
- (Thomas County) Channel Island
- (Sitka City and Borough) Channel Island
- (Madison County) Channel Island
- (Prince of Wales-Hyder Census Area) Channel Islands
- (Ketchikan Gateway Borough) Channel Islands
- (Prince of Wales-Hyder Census Area) Chapin Island
- (Sitka City and Borough) Charcoal Island
- (Perry County) Chapel Island