King William Island is an island in the Kitikmeot Region of Nunavut, which is part of the Arctic Archipelago. In area it is between 12,516 km² and 13,111 km² making it the 61st-largest island in the world and Canada's 15th-largest island. Its population, as of the 2021 census, was 1,349, all of whom live in the island's only community, Gjoa Haven.