state record · population
Population of Illinois
Illinois had an estimated population of 12,710,158 on July 1, 2024, according to the Census Bureau's Population Estimates Program.
What stands out
Illinois had an estimated population of 12,710,158 on July 1, 2024, according to the Census Bureau's Population Estimates Program. Since July 2020 that is -0.7 % (-88,930 people); since 2010 it is -1.0 %. Migration is the larger driver since 2020: net migration -117,572 against a natural change (births minus deaths) of +27,394. Among the 51 states in the United States, it ranks 6 by population. Values for 2010–2019 and 2020–2024 come from two estimate vintages benchmarked to different censuses; the 2019→2020 step is partly a rebasing.
Population and components of change
July 1 estimates; components per estimate year (July–June).
Largest counties in Illinois
By latest estimate, with change since July 2020. Each links to the county's own population record.
| County | Population | Since 2020 |
|---|---|---|
| Cook County | 5,182,617 | -1.6 % |
| DuPage County | 937,142 | +0.6 % |
| Lake County | 718,604 | +0.7 % |
| Will County | 708,583 | +1.7 % |
| Kane County | 520,997 | +0.9 % |
| McHenry County | 315,959 | +1.9 % |
| Winnebago County | 283,790 | -0.4 % |
| Madison County | 263,017 | -1.0 % |
| St. Clair County | 251,149 | -2.3 % |
| Champaign County | 212,374 | +3.0 % |
| Sangamon County | 194,345 | -1.0 % |
| Peoria County | 179,630 | -1.0 % |
| McLean County | 172,069 | +0.5 % |
| Kendall County | 143,171 | +8.2 % |
| Rock Island County | 142,731 | -1.1 % |
| Tazewell County | 129,821 | -1.1 % |
| LaSalle County | 108,390 | -0.9 % |
| Kankakee County | 106,410 | -0.9 % |
| DeKalb County | 101,335 | +1.0 % |
| Macon County | 100,737 | -2.9 % |
| Vermilion County | 71,106 | -3.9 % |
| Williamson County | 67,064 | -0.1 % |
| Adams County | 64,109 | -2.3 % |
| Whiteside County | 54,657 | -1.6 % |
| Grundy County | 53,835 | +2.5 % |
Largest cities and towns in Illinois
Incorporated places, latest estimate. The Census Bureau publishes totals only for places, no components.
| Place | Population | Since 2020 |
|---|---|---|
| Chicago city | 2,721,308 | -0.9 % |
| Aurora city | 180,710 | +0.2 % |
| Naperville city | 153,124 | +2.5 % |
| Joliet city | 151,837 | +1.0 % |
| Rockford city | 147,486 | -0.8 % |
| Elgin city | 114,701 | +0.0 % |
| Springfield city | 112,949 | -1.2 % |
| Peoria city | 111,696 | -1.1 % |
| Champaign city | 91,961 | +4.0 % |
| Waukegan city | 88,570 | -0.6 % |
| Cicero town | 82,090 | -3.3 % |
| Bloomington city | 79,232 | +0.7 % |
| Schaumburg village | 77,099 | -1.7 % |
| Evanston city | 76,006 | -2.3 % |
| Arlington Heights village | 75,596 | -2.3 % |
| Bolingbrook village | 74,756 | +1.3 % |
| Decatur city | 68,763 | -3.1 % |
| Palatine village | 65,951 | -2.5 % |
| Skokie village | 65,850 | -2.7 % |
| Des Plaines city | 58,832 | -2.7 % |
| Orland Park village | 58,020 | -0.9 % |
| Oak Lawn village | 56,531 | -2.8 % |
| Mount Prospect village | 55,460 | -2.2 % |
| Berwyn city | 55,152 | -3.2 % |
| Tinley Park village | 54,856 | -1.7 % |
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