| | Sac County | IA | 19161 | | | | | nonmetro county (rural) | farm-dependent | https://maps.google.com/?q=SacCounty+IA |
| | Scott County | IA | 19163 | | Davenport-Moline-Rock
Island, IA-IL 19340 | Davenport-Moline, IA-IL 209 | Central | metro county (urban) | nonspecialized | https://maps.google.com/?q=ScottCounty+IA |
| | Shelby County | IA | 19165 | | | | | nonmetro county (rural) | nonspecialized | https://maps.google.com/?q=ShelbyCounty+IA |
| | Sioux County | IA | 19167 | | | | | nonmetro county (rural) | manufacturing-dependent | https://maps.google.com/?q=SiouxCounty+IA |
| | Story County | IA | 19169 | | Ames, IA 11180 | Des Moines-West Des
Moines-Ames, IA 218 | Central | metro county (urban) | federal/state
government-dependent | https://maps.google.com/?q=StoryCounty+IA |
| | Tama County | IA | 19171 | | | | | nonmetro county (rural) | farm-dependent | https://maps.google.com/?q=TamaCounty+IA |
| | Taylor County | IA | 19173 | | | | | nonmetro county (rural) | farm-dependent | https://maps.google.com/?q=TaylorCounty+IA |
| | Union County | IA | 19175 | | | | | nonmetro county (rural) | manufacturing-dependent | https://maps.google.com/?q=UnionCounty+IA |
| | Van Buren County | IA | 19177 | | | | | nonmetro county (rural) | manufacturing-dependent | https://maps.google.com/?q=VanBurenCounty+IA |
| | Wapello County | IA | 19179 | | Ottumwa, IA 36900 | | Central | nonmetro county (rural) | manufacturing-dependent | https://maps.google.com/?q=WapelloCounty+IA |