| | Charles Mix County | SD | 46023 | | | | | nonmetro county (rural) | farm-dependent | https://maps.google.com/?q=CharlesMixCounty+SD |
| | Clark County | SD | 46025 | | | | | nonmetro county (rural) | farm-dependent | https://maps.google.com/?q=ClarkCounty+SD |
| | Clay County | SD | 46027 | | Vermillion, SD 46820 | | Central | nonmetro county (rural) | federal/state
government-dependent | https://maps.google.com/?q=ClayCounty+SouthDakota |
| | Codington County | SD | 46029 | | Watertown, SD 47980 | | Central | nonmetro county (rural) | nonspecialized | https://maps.google.com/?q=CodingtonCounty+SD |
| | Corson County | SD | 46031 | | | | | nonmetro county (rural) | farm-dependent | https://maps.google.com/?q=CorsonCounty+SD |
| | Custer County | SD | 46033 | | Rapid City, SD 39660 | Rapid City-Spearfish, SD 452 | Outlying | metro county (urban) | federal/state
government-dependent | https://maps.google.com/?q=CusterCounty+SD |
| | Davison County | SD | 46035 | | Mitchell, SD 33580 | | Central | nonmetro county (rural) | nonspecialized | https://maps.google.com/?q=DavisonCounty+SD |
| | Day County | SD | 46037 | | | | | nonmetro county (rural) | farm-dependent | https://maps.google.com/?q=DayCounty+SD |
| | Deuel County | SD | 46039 | | | | | nonmetro county (rural) | farm-dependent | https://maps.google.com/?q=DeuelCounty+SD |
| | Dewey County | SD | 46041 | | | | | nonmetro county (rural) | federal/state
government-dependent | https://maps.google.com/?q=DeweyCounty+SD |