| | 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 |
| | Brown County | IL | 17009 | | | | | nonmetro county (rural) | nonspecialized | https://maps.google.com/?q=BrownCounty+IL |
| | Bureau County | IL | 17011 | | Ottawa, IL 36837 | Chicago-Naperville,
IL-IN-WI 176 | Central | nonmetro county (rural) | nonspecialized | https://maps.google.com/?q=BureauCounty+Illinois |
| | Carroll County | IL | 17015 | | | | | nonmetro county (rural) | nonspecialized | https://maps.google.com/?q=CarrollCounty+IL |
| | Cass County | IL | 17017 | | | | | nonmetro county (rural) | manufacturing-dependent | https://maps.google.com/?q=CassCounty+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 |
| | Clark County | IL | 17023 | | | | | nonmetro county (rural) | manufacturing-dependent | https://maps.google.com/?q=ClarkCounty+IL |
| | Clay County | IL | 17025 | | | | | nonmetro county (rural) | manufacturing-dependent | https://maps.google.com/?q=ClayCounty+IL |
| | Coles County | IL | 17029 | | Charleston-Mattoon, IL 16660 | | Central | nonmetro county (rural) | federal/state
government-dependent | https://maps.google.com/?q=ColesCounty+IL |
| | Crawford County | IL | 17033 | | | | | nonmetro county (rural) | manufacturing-dependent | https://maps.google.com/?q=CrawfordCounty+IL |