Gil Island is an island on the North Coast of British Columbia, Canada, located on the west side of Whale Channel in the entrance to Douglas Channel, one of the main coastal inlets, on the route of the Inside Passage between Pitt Island and Princess Royal Island. It is 26 km (16 mi) long, with a width ranging from 6 to 13 km (4 to 8 mi), and an area of 231 km2 (89 sq mi). The only named summit on the mountainous island is Mount Gil, which faces the opening of Douglas Channel.