Population of Illinois 2021
POPULATION
78% of the population are white and 15% are black. About 20,000 Indians still live in Illinois today. In the 1980s, a large wave of immigrants came into the country, mostly from Asia and Latin America. A Polish minority lives in Chicago.
Top Counties by Population in Illinois
| Rank | County Name | Population | Population Density (per km²) |
| 1 | Cook County | 5,180,504 | 2,118.82 |
| 2 | DuPage County | 928,600 | 1,096.34 |
| 3 | Lake County | 700,843 | 611.02 |
| 4 | Will County | 692,321 | 320.07 |
| 5 | Kane County | 534,227 | 397.49 |
| 6 | McHenry County | 308,581 | 197.56 |
| 7 | Winnebago County | 284,092 | 213.76 |
| 8 | Madison County | 264,472 | 142.65 |
| 9 | St. Clair County | 261,070 | 153.39 |
| 10 | Champaign County | 209,994 | 81.39 |
| 11 | Sangamon County | 195,359 | 86.90 |
| 12 | Peoria County | 180,632 | 112.82 |
| 13 | McLean County | 172,839 | 56.41 |
| 14 | Rock Island County | 143,488 | 129.74 |
| 15 | Tazewell County | 132,339 | 79.10 |
| 16 | Kendall County | 127,926 | 154.31 |
| 17 | Kankakee County | 110,035 | 62.84 |
| 18 | LaSalle County | 109,441 | 37.22 |
| 19 | Macon County | 104,723 | 69.72 |
| 20 | DeKalb County | 104,154 | 63.74 |
| 21 | Vermilion County | 76,817 | 33.03 |
| 22 | Williamson County | 67,067 | 61.64 |
| 23 | Adams County | 65,702 | 29.68 |
| 24 | Jackson County | 57,430 | 37.96 |
| 25 | Whiteside County | 55,637 | 31.40 |
| 26 | Boone County | 53,588 | 73.91 |
| 27 | Grundy County | 50,983 | 47.08 |
| 28 | Ogle County | 50,934 | 25.95 |
| 29 | Coles County | 50,896 | 38.67 |
| 30 | Knox County | 50,123 | 27.04 |
| 31 | Henry County | 49,101 | 23.06 |
| 32 | Macoupin County | 45,324 | 20.30 |
| 33 | Stephenson County | 44,764 | 30.64 |
| 34 | Franklin County | 38,712 | 36.62 |
| 35 | Woodford County | 38,474 | 28.19 |
| 36 | Jefferson County | 37,831 | 25.58 |
| 37 | Clinton County | 37,650 | 30.66 |
| 38 | Marion County | 37,631 | 25.41 |
| 39 | Livingston County | 35,772 | 13.24 |
| 40 | Fulton County | 34,855 | 15.56 |
| 41 | Monroe County | 34,346 | 34.45 |
| 42 | Lee County | 34,234 | 18.26 |
| 43 | Effingham County | 34,219 | 27.64 |
| 44 | Morgan County | 33,987 | 23.10 |
| 45 | Bureau County | 33,004 | 14.66 |
| 46 | Christian County | 32,672 | 17.80 |
| 47 | Randolph County | 32,117 | 21.57 |
| 48 | McDonough County | 29,966 | 19.64 |
| 49 | Logan County | 28,936 | 18.07 |
| 50 | Montgomery County | 28,612 | 15.71 |
| 51 | Iroquois County | 27,615 | 9.55 |
| 52 | Saline County | 23,917 | 24.36 |
| 53 | Jersey County | 21,858 | 22.86 |
| 54 | Shelby County | 21,752 | 11.08 |
| 55 | Fayette County | 21,427 | 11.56 |
| 56 | Jo Daviess County | 21,377 | 13.76 |
| 57 | Perry County | 21,185 | 18.55 |
| 58 | Douglas County | 19,490 | 18.10 |
| 59 | Crawford County | 18,818 | 16.41 |
| 60 | Hancock County | 17,855 | 8.69 |
| 61 | Edgar County | 17,371 | 10.76 |
| 62 | Warren County | 17,043 | 12.14 |
| 63 | Union County | 16,852 | 15.75 |
| 64 | Bond County | 16,641 | 16.91 |
| 65 | Piatt County | 16,407 | 14.43 |
| 66 | Wayne County | 16,343 | 8.85 |
| 67 | DeWitt County | 15,780 | 15.35 |
| 68 | Lawrence County | 15,776 | 16.38 |
| 69 | Richland County | 15,774 | 16.92 |
| 70 | Pike County | 15,622 | 7.26 |
| 71 | Mercer County | 15,612 | 10.74 |
| 72 | Clark County | 15,607 | 12.02 |
| 73 | Moultrie County | 14,728 | 16.97 |
| 74 | Carroll County | 14,323 | 12.42 |
| 75 | Massac County | 14,091 | 22.95 |
| 76 | Washington County | 14,006 | 9.62 |
| 77 | White County | 13,676 | 10.69 |
| 78 | Mason County | 13,576 | 9.72 |
| 79 | Ford County | 13,275 | 10.57 |
| 80 | Clay County | 13,264 | 10.94 |
| 81 | Greene County | 13,055 | 9.29 |
| 82 | Johnson County | 12,467 | 14.04 |
| 83 | Menard County | 12,299 | 15.13 |
| 84 | Cass County | 12,271 | 12.64 |
| 85 | Wabash County | 11,560 | 20.00 |
| 86 | Marshall County | 11,545 | 11.55 |
| 87 | Cumberland County | 10,819 | 12.10 |
| 88 | Jasper County | 9,622 | 7.52 |
| 89 | Hamilton County | 8,174 | 7.27 |
| 90 | Schuyler County | 6,918 | 6.11 |
| 91 | Henderson County | 6,720 | 6.86 |
| 92 | Brown County | 6,567 | 8.31 |
| 93 | Edwards County | 6,403 | 11.14 |
| 94 | Alexander County | 6,071 | 9.97 |
| 95 | Putnam County | 5,751 | 13.89 |
| 96 | Pulaski County | 5,474 | 10.63 |
| 97 | Stark County | 5,438 | 7.29 |
| 98 | Gallatin County | 5,069 | 6.08 |
| 99 | Scott County | 4,937 | 7.63 |
| 100 | Calhoun County | 4,813 | 7.35 |
| 101 | Pope County | 4,223 | 4.43 |
| 102 | Hardin County | 3,921 | 8.56 |