Saint Onge was laid out in 1881.[6] The community was named for Henry St. Onge, a pioneer settler.[7] A post office called Saint Onge has been in operation since 1881.[8] Saint Onge has been assigned the ZIP code of 57779.[9]
Geography
St. Onge is in northeastern Lawrence County, along South Dakota Highway 34, which leads northwest 12 miles (19 km) to Belle Fourche and southeast 7 miles (11 km) to Interstate 90 at Whitewood. Spearfish, the largest community in the county, is 12 miles (19 km) to the southwest.
According to the U.S. Census Bureau, the St. Onge CDP has an area of 1.4 square miles (3.5 km2), all land.[10] False Bottom Creek forms the western edge of the community, and its tributary Dry Creek forms the northeastern edge. False Bottom Creek flows northwest to the Redwater River, which in turn is a tributary of the Belle Fourche River, flowing east to the Missouri.