| | Clay County | IA | 19041 | | Spencer, IA 43980 | Spencer-Spirit Lake, IA 517 | Central | nonmetro county (rural) | nonspecialized | https://maps.google.com/?q=ClayCounty+IA |
| | Clayton County | IA | 19043 | | | | | nonmetro county (rural) | nonspecialized | https://maps.google.com/?q=ClaytonCounty+IA |
| | Dallas County | IA | 19049 | | Des Moines-West Des
Moines, IA 19780 | Des Moines-West Des
Moines-Ames, IA 218 | Central | metro county (urban) | nonspecialized | https://maps.google.com/?q=DallasCounty+IA |
| | Decatur County | IA | 19053 | | | | | nonmetro county (rural) | nonspecialized | https://maps.google.com/?q=DecaturCounty+IA |
| | Dubuque County | IA | 19061 | | Dubuque, IA 20220 | | Central | metro county (urban) | nonspecialized | https://maps.google.com/?q=DubuqueCounty+IA |
| | Emmet County | IA | 19063 | | | | | nonmetro county (rural) | nonspecialized | https://maps.google.com/?q=EmmetCounty+IA |
| | Fayette County | IA | 19065 | | | | | nonmetro county (rural) | nonspecialized | https://maps.google.com/?q=FayetteCounty+IA |
| | Jackson County | IA | 19097 | | | | | nonmetro county (rural) | nonspecialized | https://maps.google.com/?q=JacksonCounty+IA |
| | Jasper County | IA | 19099 | | Des Moines-West Des
Moines, IA 19780 | Des Moines-West Des
Moines-Ames, IA 218 | Outlying | nonmetro county (rural) | nonspecialized | https://maps.google.com/?q=JasperCounty+Iowa |
| | Jefferson County | IA | 19101 | | | | | nonmetro county (rural) | nonspecialized | https://maps.google.com/?q=JeffersonCounty+Iowa |