Sweet Grass County is in Yellowstone Country Montana. Of the 56 counties in the Treasure State, 1,862-square-mile Sweet Grass County ranks 37th by size. Recent listings of residential land and property for sale in Montana's Sweet Grass County totals nearly 1,000 acres and a combined market value of nearly $28 million. The most common type of land for sale by combined acreage in Sweet Grass County is house. The average price of residential acreage for sale in Sweet Grass County was $1 million. Browse all residential land and rural property for sale in Montana to find residential land and properties that suit your lifestyle needs, from existing residential homes and estates to land ready for future residential-property development.