Beaver Island is an island in Lake Michigan in the U.S. state of Michigan. At 55.8 sq mi, it is the largest island in Lake Michigan and the third largest island in Michigan after Isle Royale and Drummond Island. The island is located approximately 32 miles from the city of Charlevoix. Beaver Island had a total population of 616 at the 2020 census. Beaver Island is part of Charlevoix County.