Frontier is an unincorporated community in Koochiching County, Minnesota, United States; located along the Rainy River.The community is located between International Falls and Baudette on State Highway 11 (MN 11). Frontier is located within Northwest Koochiching Unorganized Territory.The Rainy River and Whitefish Creek meet at Frontier.Frontier is located 18 miles east of Baudette; and 50 miles west of International Falls.