| | | Tazewell County | IL | 17179 | | Peoria, IL 37900 | Peoria-Canton, IL 427 | Central | metro county (urban) | manufacturing-dependent | https://maps.google.com/?q=TazewellCounty+IL |
| | | Woodford County | IL | 17203 | | Peoria, IL 37900 | Peoria-Canton, IL 427 | Central | metro county (urban) | manufacturing-dependent | https://maps.google.com/?q=WoodfordCounty+IL |
| | | Adams County | IL | 17001 | | Quincy, IL-MO 39500 | Quincy-Hannibal, IL-MO 448 | Central | nonmetro county (rural) | nonspecialized | https://maps.google.com/?q=AdamsCounty+IL |
| | | Boone County | IL | 17007 | | Rockford, IL 40420 | Rockford-Freeport-Rochelle,
IL 466 | Central | metro county (urban) | manufacturing-dependent | https://maps.google.com/?q=BooneCounty+IL |
| | | Ogle County | IL | 17141 | | Rochelle, IL 40300 | Rockford-Freeport-Rochelle,
IL 466 | Central | nonmetro county (rural) | nonspecialized | https://maps.google.com/?q=OgleCounty+IL |
| | | Stephenson County | IL | 17177 | | Freeport, IL 23300 | Rockford-Freeport-Rochelle,
IL 466 | Central | nonmetro county (rural) | manufacturing-dependent | https://maps.google.com/?q=StephensonCounty+IL |
| | | Winnebago County | IL | 17201 | | Rockford, IL 40420 | Rockford-Freeport-Rochelle,
IL 466 | Central | metro county (urban) | manufacturing-dependent | https://maps.google.com/?q=WinnebagoCounty+IL |
| | | Christian County | IL | 17021 | | Taylorville, IL 45380 | Springfield-Jacksonville-Lincoln,
IL 522 | Central | nonmetro county (rural) | nonspecialized | https://maps.google.com/?q=ChristianCounty+IL |
| | | Logan County | IL | 17107 | | Lincoln, IL 30660 | Springfield-Jacksonville-Lincoln,
IL 522 | Central | nonmetro county (rural) | nonspecialized | https://maps.google.com/?q=LoganCounty+IL |
| | | Menard County | IL | 17129 | | Springfield, IL 44100 | Springfield-Jacksonville-Lincoln,
IL 522 | Outlying | metro county (urban) | farm-dependent | https://maps.google.com/?q=MenardCounty+IL |
