Illinois (IL) on the US Map

Map of Illinois Counties
Below is a map of the 102 counties of Illinois (you can click on the map to enlarge it and to see the major city in each state).

Click on any of the counties on the map to see the county’s population, economic data, time zone, and zip code (the data will appear below the map). Data is sourced from the US Census 2021.
List of the Counties of Illinois:
County | Population | Per sq. km | Largest City |
---|---|---|---|
Adams County | 65,878 | 29.74 | Quincy |
Alexander County | 5,488 | 9 | Cairo |
Bond County | 16,804 | 17.06 | Greenville |
Boone County | 53,592 | 73.71 | Belvidere |
Brown County | 6,330 | 7.99 | Mount Sterling |
Bureau County | 33,338 | 14.81 | Peru |
Calhoun County | 4,537 | 6.9 | Hardin |
Carroll County | 15,586 | 13.51 | Savanna |
Cass County | 13,058 | 13.42 | Beardstown |
Champaign County | 206,583 | 80.07 | Champaign |
Christian County | 34,038 | 18.52 | Taylorville |
Clark County | 15,587 | 12 | Marshall |
Clay County | 13,313 | 10.98 | Flora |
Clinton County | 37,048 | 30.18 | Centralia |
Coles County | 47,542 | 36.11 | Charleston |
Cook County | 5,265,398 | 2151.47 | Chicago |
Crawford County | 18,825 | 16.38 | Robinson |
Cumberland County | 10,528 | 11.75 | Casey |
De Witt County | 15,653 | 15.2 | Clinton |
DeKalb County | 100,922 | 61.72 | DeKalb |
Douglas County | 19,708 | 18.26 | Tuscola |
DuPage County | 934,094 | 1100.23 | Chicago |
Edgar County | 16,998 | 10.53 | Paris |
Edwards County | 6,233 | 10.82 | Albion |
Effingham County | 34,576 | 27.88 | Effingham |
Fayette County | 21,514 | 11.59 | Vandalia |
Ford County | 13,589 | 10.8 | Paxton |
Franklin County | 38,068 | 35.94 | West Frankfort |
Fulton County | 34,022 | 15.17 | Canton |
Gallatin County | 5,038 | 6.02 | Shawneetown |
Greene County | 12,187 | 8.66 | Carrollton |
Grundy County | 52,364 | 48.35 | Morris |
Hamilton County | 8,021 | 7.13 | McLeansboro |
Hancock County | 17,750 | 8.63 | Hamilton |
Hardin County | 3,700 | 8.05 | Rosiclare |
Henderson County | 6,485 | 6.61 | Oquawka |
Henry County | 49,412 | 23.18 | Kewanee |
Iroquois County | 27,362 | 9.45 | Watseka |
Jackson County | 53,676 | 35.51 | Carbondale |
Jasper County | 9,324 | 7.28 | Newton |
Jefferson County | 37,362 | 25.25 | Mount Vernon |
Jersey County | 21,533 | 22.5 | Jerseyville |
Jo Daviess County | 21,995 | 14.13 | Galena |
Johnson County | 13,238 | 14.87 | Vienna |
Kane County | 518,648 | 385.57 | Aurora |
Kankakee County | 108,104 | 61.7 | Kankakee |
Kendall County | 130,757 | 157.65 | Aurora |
Knox County | 50,193 | 27.05 | Galesburg |
Lake County | 714,484 | 621.85 | Round Lake Beach |
LaSalle County | 109,986 | 37.41 | Ottawa |
Lawrence County | 15,465 | 16.04 | Lawrenceville |
Lee County | 34,373 | 18.31 | Dixon |
Livingston County | 35,902 | 13.28 | Streator |
Logan County | 28,238 | 17.64 | Lincoln |
Macon County | 104,331 | 69.38 | Decatur |
Macoupin County | 45,152 | 20.2 | Carlinville |
Madison County | 266,112 | 143.6 | Alton |
Marion County | 37,781 | 25.48 | Centralia |
Marshall County | 11,781 | 11.76 | Henry |
Mason County | 13,225 | 9.47 | Havana |
Massac County | 14,280 | 23.25 | Metropolis |
McDonough County | 27,743 | 18.18 | Macomb |
McHenry County | 310,749 | 198.84 | Crystal Lake |
McLean County | 171,455 | 55.95 | Bloomington |
Menard County | 12,343 | 15.16 | Petersburg |
Mercer County | 15,779 | 10.86 | Aledo |
Monroe County | 34,732 | 34.8 | Columbia |
Montgomery County | 28,482 | 15.63 | Litchfield |
Morgan County | 33,189 | 22.52 | Jacksonville |
Moultrie County | 14,634 | 16.82 | Sullivan |
Ogle County | 51,787 | 26.36 | Rockford |
Peoria County | 182,439 | 113.85 | Peoria |
Perry County | 21,158 | 18.49 | Du Quoin |
Piatt County | 16,664 | 14.65 | Monticello |
Pike County | 14,923 | 6.93 | Pittsfield |
Pope County | 3,820 | 4 | Golconda |
Pulaski County | 5,279 | 10.23 | Mounds |
Putnam County | 5,638 | 13.6 | Granville |
Randolph County | 30,632 | 20.56 | Chester |
Richland County | 15,876 | 17.03 | Olney |
Rock Island County | 144,694 | 130.68 | Moline |
Saline County | 23,869 | 24.25 | Harrisburg |
Sangamon County | 196,759 | 87.5 | Springfield |
Schuyler County | 6,953 | 6.14 | Rushville |
Scott County | 4,923 | 7.58 | Winchester |
Shelby County | 21,160 | 10.77 | Pana |
St. Clair County | 258,597 | 151.8 | Belleville |
Stark County | 5,436 | 7.29 | Wyoming |
Stephenson County | 44,817 | 30.67 | Freeport |
Tazewell County | 131,977 | 78.82 | Pekin |
Union County | 17,259 | 16.12 | Anna |
Vermilion County | 74,953 | 32.22 | Danville |
Wabash County | 11,414 | 19.73 | Mount Carmel |
Warren County | 16,887 | 12.02 | Monmouth |
Washington County | 13,827 | 9.49 | Centralia |
Wayne County | 16,250 | 8.79 | Fairfield |
White County | 13,959 | 10.89 | Carmi |
Whiteside County | 55,932 | 31.57 | Sterling |
Will County | 696,403 | 321.68 | Aurora |
Williamson County | 67,271 | 61.81 | Marion |
Winnebago County | 285,471 | 214.83 | Rockford |
Woodford County | 38,571 | 28.23 | Eureka |