In 1976, the route was designated as South Dakota 49, with the number extended to the junction with South Dakota Highway 44. In 1984, the route was further extended to Colome, at the junction of U.S. 18 and U.S. 183.
In 1976, the route was designated as South Dakota 49, with its number reaching the junction of South Dakota Highway 44. In 1984, the route was extended to Colome, at the intersection of U.S. 18 and U.S. 183.