Data / Rankings / Population aged 18 to 64 / Counties in Illinois

Counties in Illinois by population aged 18 to 64, 2025

Champaign County had the highest population aged 18 to 64 of 102 counties in 2025, at 66.4%. Hardin County had the lowest, at 49.2%. The median was 55.9% and the figure for Illinois was 60.7%. Source: the U.S. Census Bureau.

Highest66.4Champaign County
Lowest49.2Hardin County
Median55.9102 counties
Illinois60.7History

Top 40 counties, 2025

Champaign County: 66.4 %Champaign County66.4Brown County: 65.7 %Brown County65.7Cook County: 63.4 %Cook County63.4McLean County: 63.2 %McLean County63.2Bond County: 62.5 %Bond County62.5DeKalb County: 62.3 %DeKalb County62.3Jackson County: 62 %Jackson County62Kendall County: 61.9 %Kendall County61.9Johnson County: 61.3 %Johnson County61.3Will County: 61 %Will County61Lake County: 60.3 %Lake County60.3Kane County: 60.1 %Kane County60.1Grundy County: 60 %Grundy County60Coles County: 59.8 %Coles County59.8McHenry County: 59.6 %McHenry County59.6DuPage County: 59.4 %DuPage County59.4Logan County: 59.3 %Logan County59.3McDonough County: 59.2 %McDonough County59.2Perry County: 59.2 %Perry County59.2Lawrence County: 59.1 %Lawrence County59.1Madison County: 58.9 %Madison County58.9Boone County: 58.8 %Boone County58.8Fayette County: 58.7 %Fayette County58.7St. Clair County: 58.6 %St. Clair County58.6Christian County: 58.3 %Christian County58.3Morgan County: 58.1 %Morgan County58.1Randolph County: 58.1 %Randolph County58.1Kankakee County: 58 %Kankakee County58Crawford County: 57.9 %Crawford County57.9Lee County: 57.9 %Lee County57.9Winnebago County: 57.7 %Winnebago County57.7Sangamon County: 57.6 %Sangamon County57.6Fulton County: 57.6 %Fulton County57.6Cass County: 57.5 %Cass County57.5Clinton County: 57.5 %Clinton County57.5Peoria County: 57.3 %Peoria County57.3Montgomery County: 57.3 %Montgomery County57.3Williamson County: 57.3 %Williamson County57.3Tazewell County: 57.2 %Tazewell County57.2LaSalle County: 57 %LaSalle County57
%. Source: Invokely calculation with data from U.S. Census Bureau. Retrieved 2026-10-12.

Full ranking

RankCounties2025 (%)Change on 2024
1Champaign County66.4-0.1 pts
2Brown County65.7-0.5 pts
3Cook County63.4-0 pts
4McLean County63.2-0.2 pts
5Bond County62.5+0.6 pts
6DeKalb County62.3-0.1 pts
7Jackson County62-0.1 pts
8Kendall County61.9+0.4 pts
9Johnson County61.3-0.6 pts
10Will County61-0.1 pts
11Lake County60.3-0.2 pts
12Kane County60.1-0.1 pts
13Grundy County60+0.1 pts
14Coles County59.8-0.5 pts
15McHenry County59.6-0.4 pts
16DuPage County59.4-0.3 pts
17Logan County59.3-0.1 pts
18McDonough County59.2-0.5 pts
19Perry County59.2-0.3 pts
20Lawrence County59.1+0.4 pts
21Madison County58.9-0.2 pts
22Boone County58.8-0 pts
23Fayette County58.7-0.3 pts
24St. Clair County58.6-0.1 pts
25Christian County58.3-0.1 pts
26Morgan County58.1-0.3 pts
27Randolph County58.1-0.1 pts
28Kankakee County58-0.2 pts
29Crawford County57.9-0.3 pts
30Lee County57.9-0.3 pts
31Winnebago County57.7-0.2 pts
32Sangamon County57.6-0.3 pts
33Fulton County57.6-0 pts
34Cass County57.5+0.1 pts
35Clinton County57.5-0.3 pts
36Peoria County57.3-0.1 pts
37Montgomery County57.3-0.1 pts
38Williamson County57.3-0.3 pts
39Tazewell County57.2+0.1 pts
40LaSalle County57-0.3 pts
41Ogle County56.9-0.2 pts
42De Witt County56.8-0.1 pts
43Jersey County56.7-0.1 pts
44Knox County56.6-0.1 pts
45Carroll County56.2-0.7 pts
46Rock Island County56.2-0.4 pts
47Livingston County56.1-0.3 pts
48Warren County56.1-0 pts
49Macoupin County56-0.1 pts
50Monroe County56-0.3 pts
51Jefferson County55.9-0.3 pts
52Massac County55.8-0.2 pts
53Menard County55.7+0.1 pts
54Effingham County55.6-0.2 pts
55Adams County55.5-0.3 pts
56Union County55.5-0 pts
57Richland County55.5-0.2 pts
58Franklin County55.4-0.2 pts
59Vermilion County55.4-0.2 pts
60Macon County55.3-0.1 pts
61Saline County55.2-0.1 pts
62Washington County55.2-0.4 pts
63Mercer County55.2-0.3 pts
64Bureau County55.2-0.3 pts
65Mason County55.2-0.5 pts
66Clark County55.2-0.3 pts
67Douglas County55.1-0.3 pts
68Greene County55-0.2 pts
69Pulaski County550 pts
70Ford County54.8-0.3 pts
71Putnam County54.8-0.7 pts
72Gallatin County54.8+0.1 pts
73White County54.8+0.2 pts
74Wabash County54.7-0.1 pts
75Whiteside County54.6-0.2 pts
76Henry County54.6-0.3 pts
77Woodford County54.6-0.4 pts
78Hamilton County54.5-0.1 pts
79Schuyler County54.5-0.7 pts
80Stark County54.4-0.1 pts
81Piatt County54.4-0.3 pts
82Marion County54.4-0.2 pts
83Wayne County54.3-0.1 pts
84Edwards County54.3-0.5 pts
85Cumberland County54.2-0.3 pts
86Scott County54.2-0.3 pts
87Pope County54.2+0.4 pts
88Iroquois County54-0.3 pts
89Clay County54-0.3 pts
90Edgar County54-0.3 pts
91Marshall County53.9-0.1 pts
92Pike County53.9+0.2 pts
93Jasper County53.6-0.2 pts
94Moultrie County53.5-0.2 pts
95Stephenson County53.5-0.2 pts
96Shelby County53.5-0.3 pts
97Alexander County53.2-0.1 pts
98Calhoun County52.3-0.9 pts
99Hancock County52.3-0.3 pts
100Henderson County51.7-0.3 pts
101Jo Daviess County50.8-0.3 pts
102Hardin County49.2-0.9 pts

Other periods

About this ranking

Residents aged 18 to 64 as a percentage of total population on 1 July. United States: Census Bureau county population estimates by age; states and the nation are sums of their counties.

Not comparable with working-age shares for ages 15 to 64 used in EU and World Bank statistics.

Every value in the ranking comes from the same publisher and the same period, so the counties are compared on one definition. Equal values share a rank.

How to cite

U.S. Census Bureau. Population Estimates Program, county population by age and sex: residents aged 18 to 64 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties. https://www.census.gov/programs-surveys/popest/data/data-sets.html. Retrieved 2026-10-12.

Use this data in your AI agent

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Rank Counties in Illinois by population aged 18 to 64 using official data, and cite the source.
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Questions

Which county has the highest population aged 18 to 64?

Champaign County, with 66.4% in 2025, according to the U.S. Census Bureau.

Which county has the lowest population aged 18 to 64?

Hardin County, with 49.2% in 2025.

Where does this ranking come from?

Every value comes from one source and one period, so the places are comparable: U.S. Census Bureau, Population Estimates Program, county population by age and sex: residents aged 18 to 64 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties. Retrieved 2026-10-12.

Population aged 18 to 64: other rankings

Counties in Illinois: more rankings