Sweet Grass (also Sweetgrass ) is a census-designated place and unincorporated community in Toole County, Montana, United States, on the Canada–US border. It is the northern terminus of Interstate 15, an important route connecting western Canada, the western United States, and Mexico. The population was 65 according to the 2020 census. In 2004, a joint border facility opened at the Sweetgrass port of entry and Coutts, Alberta, housing both Canadian and American federal authorities. Fire service is provided through the volunteer fire department in Coutts.

Demographics

Climate

Sweet Grass has a semi-arid climate (Köppen BSk) that closely borders a humid continental climate (Köppen Dwb).