Gallatin County is in Yellowstone Country Montana. Of the 56 counties in the state, 2,633-square-mile Gallatin County ranks 24th by size. A recent survey of Land Network data totals almost 4,000 acres of residential land and property for sale in Montana's Gallatin County, which is valued at a combined $749 million. The average price of residential land for sale in Gallatin County was $3 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.