Belfry is a census-designated place (CDP) in Carbon County, Montana, United States. It is an unincorporated town, and is part of the Billings, Montana Metropolitan Statistical Area. The population was 193 at the 2020 census, down from 218 in the 2010 census. It is located approximately 11 miles (18 km) from the Wyoming border, roughly halfway between Billings, Montana and Cody, Wyoming.