Towns
| State | City/Town | Town Title |
|---|---|---|
| Illinois | Chrisman | Chrisman, IL |
| Illinois | Christopher | Christopher, IL |
| Illinois | Cicero | Cicero, IL |
| Illinois | Cisco | Cisco, IL |
| Illinois | Cisne | Cisne, IL |
| Illinois | Cissna Park | Cissna Park, IL |
| Illinois | Clare | Clare, IL |
| Illinois | Claremont | Claremont, IL |
| Illinois | Clarendon Hills | Clarendon Hills, IL |
| Illinois | Clay City | Clay City, IL |
| Illinois | Clayton | Clayton, IL |
| Illinois | Claytonville | Claytonville, IL |
| Illinois | Clifton | Clifton, IL |
| Illinois | Clinton | Clinton, IL |
| Illinois | Coal City | Coal City, IL |
| Illinois | Coal Valley | Coal Valley, IL |
| Illinois | Coatsburg | Coatsburg, IL |
| Illinois | Cobden | Cobden, IL |
| Illinois | Coello | Coello, IL |
| Illinois | Coffeen | Coffeen, IL |
| Illinois | Colchester | Colchester, IL |
| Illinois | Colfax | Colfax, IL |
| Illinois | Collinsville | Collinsville, IL |
| Illinois | Collison | Collison, IL |
| Illinois | Colona | Colona, IL |