North Spearfish is a census-designated place in Lawrence County, South Dakota, United States. The population was 2,366 at the 2020 census. North Spearfish is located in northern Lawrence County at 44°30′29″N 103°53′7″W / 44.50806°N 103.88528°W, on the northwest side of the city of Spearfish, the largest community in the county. Interstate 90 runs …North Spearfish is a census-designated place in Lawrence County, South Dakota, United States. The population was 2,366 at the 2020 census. North Spearfish is located in northern Lawrence County at 44°30′29″N 103°53′7″W / 44.50806°N 103.88528°W, on the northwest side of the city of Spearfish, the largest community in the county. Interstate 90 runs along the northern edge of the CDP, with access from Exit 8. I-90 leads southeast 50 miles to Rapid City and west 90 miles to Gillette, Wyoming. U.S. Route 85 departs from I-90 at the northeast corner of North Spearfish, leading north 10 miles to Belle Fourche.