South Dakota Highway 158

South Dakota Highway 158 (SD 158) is a 9.150 mi state highway in Vernon Township, Grant County, South Dakota, United States. It travels from an intersection with SD 15 and SD 20 to the Minnesota state line, where it continues as County State-Aid Highway 44 (CSAH 44) in Lac qui Parle County.

Route description
SD 158 begins at an intersection with SD 15 and SD 20 north of La Bolt and treks east through flat farmland. The highway continues east for approximately 9 mi before curving to the northeast and ending at the Minnesota state line, continuing for 1.94 mi as CSAH 44, before terminating at CSAH 7. The route has a speed limit of 65 mph for its entire duration.

SD 158 is maintained by SDDOT. In 2012, the traffic on the highway was measured in average annual daily traffic, and SD 158 had an average of 235 vehicles. The designation is not a part of the National Highway System, a system of highways important to the nation's defense, economy, and mobility.