Montreal is a city in Iron County, Wisconsin, United States. The population was 807 at the 2010 census. The neighborhood of Gile is part of the …Montreal is a city in Iron County, Wisconsin, United States. The population was 807 at the 2010 census. The neighborhood of Gile is part of the city; however, it still has its own post office and ZIP code: 54550. Like Gile, the former unincorporated community of Germania has also been annexed by the city.