| | Alexander County | IL | 17003 | | Cape Girardeau, MO-IL 16020 | Cape Girardeau-Sikeston,
MO-IL 164 | Outlying | metro county (urban) | federal/state
government-dependent | https://maps.google.com/?q=AlexanderCounty+IL |
| | Bond County | IL | 17005 | | St. Louis, MO-IL 41180 | St. Louis-St.
Charles-Farmington, MO-IL 476 | Outlying | metro county (urban) | federal/state
government-dependent | https://maps.google.com/?q=BondCounty+IL |
| | Calhoun County | IL | 17013 | | St. Louis, MO-IL 41180 | St. Louis-St.
Charles-Farmington, MO-IL 476 | Outlying | metro county (urban) | farm-dependent | https://maps.google.com/?q=CalhounCounty+IL |
| | Clinton County | IL | 17027 | | St. Louis, MO-IL 41180 | St. Louis-St.
Charles-Farmington, MO-IL 476 | Outlying | metro county (urban) | nonspecialized | https://maps.google.com/?q=ClintonCounty+IL |
| | Cumberland County | IL | 17035 | | Effingham, IL 20820 | | Outlying | nonmetro county (rural) | nonspecialized | https://maps.google.com/?q=CumberlandCounty+IL |
| | DeKalb County | IL | 17037 | Elgin, IL 20994 | Chicago-Naperville-Elgin,
IL-IN 16980 | Chicago-Naperville,
IL-IN-WI 176 | Outlying | metro county (urban) | federal/state
government-dependent | https://maps.google.com/?q=DeKalbCounty+IL |
| | Ford County | IL | 17053 | | Champaign-Urbana, IL 16580 | Champaign-Urbana-Denville,
IL 169 | Outlying | metro county (urban) | nonspecialized | https://maps.google.com/?q=FordCounty+IL |
| | Grundy County | IL | 17063 | Chicago-Naperville-Schaumburg,
IL 16984 | Chicago-Naperville-Elgin,
IL-IN 16980 | Chicago-Naperville,
IL-IN-WI 176 | Outlying | metro county (urban) | nonspecialized | https://maps.google.com/?q=GrundyCounty+IL |
| | Henderson County | IL | 17071 | | Burlington, IA-IL 15460 | Burlington-Fort Madison,
IA-IL 161 | Outlying | nonmetro county (rural) | farm-dependent | https://maps.google.com/?q=HendersonCounty+IL |
| | Henry County | IL | 17073 | | Davenport-Moline-Rock
Island, IA-IL 19340 | Davenport-Moline, IA-IL 209 | Outlying | metro county (urban) | nonspecialized | https://maps.google.com/?q=HenryCounty+IL |