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

Counties in Illinois by population aged 18 to 64

Champaign County had the highest population aged 18 to 64 of 102 counties in 2021, at 67.1%. Hardin County had the lowest, at 52.2%. The median was 57.3% and the figure for Illinois was 61.4%. Source: the U.S. Census Bureau.

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Highest67.1Champaign County
Lowest52.2Hardin County
Median57.3102 counties
Illinois61.4History

Map of counties, 2021

Adams County: 56.7 %Alexander County: 55.1 %Bond County: 62.8 %Boone County: 59.1 %Brown County: 67 %Bureau County: 56.4 %Calhoun County: 53.9 %Carroll County: 57.7 %Cass County: 57.8 %Champaign County: 67.1 %Christian County: 59.2 %Clark County: 56.1 %Clay County: 55.5 %Clinton County: 59.4 %Coles County: 61.8 %Cook County: 63.6 %Crawford County: 57.8 %Cumberland County: 56 %DeKalb County: 63.2 %De Witt County: 57.8 %Douglas County: 56.3 %DuPage County: 60.8 %Edgar County: 55.6 %Edwards County: 55 %Effingham County: 57 %Fayette County: 59.7 %Ford County: 55.9 %Franklin County: 56.5 %Fulton County: 58.1 %Gallatin County: 54.9 %Greene County: 55.8 %Grundy County: 60.1 %Hamilton County: 55.4 %Hancock County: 54.2 %Hardin County: 52.2 %Henderson County: 54.1 %Henry County: 55.7 %Iroquois County: 55.4 %Jackson County: 63 %Jasper County: 55.5 %Jefferson County: 57.5 %Jersey County: 58.1 %Jo Daviess County: 52.7 %Johnson County: 63.3 %Kane County: 60.4 %Kankakee County: 59.2 %Kendall County: 61 %Knox County: 57.4 %Lake County: 61.1 %LaSalle County: 58.8 %Lawrence County: 61.4 %Lee County: 59.8 %Livingston County: 57.8 %Logan County: 59.8 %McDonough County: 61.9 %McHenry County: 61.2 %McLean County: 63.8 %Macon County: 56.6 %Macoupin County: 57.2 %Madison County: 60.1 %Marion County: 55.4 %Marshall County: 55.5 %Mason County: 56.4 %Massac County: 56.2 %Menard County: 56.7 %Mercer County: 56.3 %Monroe County: 58 %Montgomery County: 58.3 %Morgan County: 60.1 %Moultrie County: 54.4 %Ogle County: 58.1 %Peoria County: 58.4 %Perry County: 59.5 %Piatt County: 56.3 %Pike County: 54 %Pope County: 54.3 %Pulaski County: 55.7 %Putnam County: 57.4 %Randolph County: 59.6 %Richland County: 55.4 %Rock Island County: 57.5 %St. Clair County: 59.4 %Saline County: 55.8 %Sangamon County: 59 %Schuyler County: 57 %Scott County: 56 %Shelby County: 54.8 %Stark County: 54.9 %Stephenson County: 54.6 %Tazewell County: 57.4 %Union County: 56.5 %Vermilion County: 56.5 %Wabash County: 55.7 %Warren County: 57.4 %Washington County: 56.8 %Wayne County: 54.8 %White County: 55 %Whiteside County: 55.8 %Will County: 61.6 %Williamson County: 57.9 %Winnebago County: 58.7 %Woodford County: 56.1 %
  • Under 55
  • 55 to 56
  • 56 to 57
  • 57 to 58
  • 58 to 60
  • 60 and over
%, 2021. Source: Invokely calculation with data from U.S. Census Bureau. Boundaries: U.S. Census Bureau cartographic boundary files.

Top 40 counties, 2021

Champaign County: 67.1 %Champaign County67.1Brown County: 67 %Brown County67McLean County: 63.8 %McLean County63.8Cook County: 63.6 %Cook County63.6Johnson County: 63.3 %Johnson County63.3DeKalb County: 63.2 %DeKalb County63.2Jackson County: 63 %Jackson County63Bond County: 62.8 %Bond County62.8McDonough County: 61.9 %McDonough County61.9Coles County: 61.8 %Coles County61.8Will County: 61.6 %Will County61.6Lawrence County: 61.4 %Lawrence County61.4McHenry County: 61.2 %McHenry County61.2Lake County: 61.1 %Lake County61.1Kendall County: 61 %Kendall County61DuPage County: 60.8 %DuPage County60.8Kane County: 60.4 %Kane County60.4Morgan County: 60.1 %Morgan County60.1Madison County: 60.1 %Madison County60.1Grundy County: 60.1 %Grundy County60.1Logan County: 59.8 %Logan County59.8Lee County: 59.8 %Lee County59.8Fayette County: 59.7 %Fayette County59.7Randolph County: 59.6 %Randolph County59.6Perry County: 59.5 %Perry County59.5St. Clair County: 59.4 %St. Clair County59.4Clinton County: 59.4 %Clinton County59.4Kankakee County: 59.2 %Kankakee County59.2Christian County: 59.2 %Christian County59.2Boone County: 59.1 %Boone County59.1Sangamon County: 59 %Sangamon County59LaSalle County: 58.8 %LaSalle County58.8Winnebago County: 58.7 %Winnebago County58.7Peoria County: 58.4 %Peoria County58.4Montgomery County: 58.3 %Montgomery County58.3Fulton County: 58.1 %Fulton County58.1Jersey County: 58.1 %Jersey County58.1Ogle County: 58.1 %Ogle County58.1Monroe County: 58 %Monroe County58Williamson County: 57.9 %Williamson County57.9Champaign County: 67.1 %Champaign County67.1Brown County: 67 %Brown County67McLean County: 63.8 %McLean County63.8Cook County: 63.6 %Cook County63.6Johnson County: 63.3 %Johnson County63.3DeKalb County: 63.2 %DeKalb County63.2Jackson County: 63 %Jackson County63Bond County: 62.8 %Bond County62.8McDonough County: 61.9 %McDonough County61.9Coles County: 61.8 %Coles County61.8Will County: 61.6 %Will County61.6Lawrence County: 61.4 %Lawrence County61.4McHenry County: 61.2 %McHenry County61.2Lake County: 61.1 %Lake County61.1Kendall County: 61 %Kendall County61DuPage County: 60.8 %DuPage County60.8Kane County: 60.4 %Kane County60.4Morgan County: 60.1 %Morgan County60.1Madison County: 60.1 %Madison County60.1Grundy County: 60.1 %Grundy County60.1Logan County: 59.8 %Logan County59.8Lee County: 59.8 %Lee County59.8Fayette County: 59.7 %Fayette County59.7Randolph County: 59.6 %Randolph County59.6Perry County: 59.5 %Perry County59.5St. Clair County: 59.4 %St. Clair County59.4Clinton County: 59.4 %Clinton County59.4Kankakee County: 59.2 %Kankakee County59.2Christian County: 59.2 %Christian County59.2Boone County: 59.1 %Boone County59.1Sangamon County: 59 %Sangamon County59LaSalle County: 58.8 %LaSalle County58.8Winnebago County: 58.7 %Winnebago County58.7Peoria County: 58.4 %Peoria County58.4Montgomery County: 58.3 %Montgomery County58.3Fulton County: 58.1 %Fulton County58.1Jersey County: 58.1 %Jersey County58.1Ogle County: 58.1 %Ogle County58.1Monroe County: 58 %Monroe County58Williamson County: 57.9 %Williamson County57.9
%. Source: Invokely calculation with data from U.S. Census Bureau. Retrieved 2026-10-12.

Full ranking

RankCounties2021 (%)Change on 2020
1Champaign County67.1-0.3 pts
2Brown County67+0.3 pts
3McLean County63.8-0.1 pts
4Cook County63.6-0.3 pts
5Johnson County63.3+0.7 pts
6DeKalb County63.2-0 pts
7Jackson County63-0.4 pts
8Bond County62.8-0.3 pts
9McDonough County61.9+0.1 pts
10Coles County61.8+0.2 pts
11Will County61.6+0.1 pts
12Lawrence County61.4-0.2 pts
13McHenry County61.2-0.2 pts
14Lake County61.1-0 pts
15Kendall County61+0.3 pts
16DuPage County60.8-0.2 pts
17Kane County60.40 pts
18Morgan County60.1-0.1 pts
19Madison County60.1-0.2 pts
20Grundy County60.1+0.2 pts
21Logan County59.8-0.7 pts
22Lee County59.8-0.3 pts
23Fayette County59.7-1 pts
24Randolph County59.6-0.1 pts
25Perry County59.5-0.5 pts
26St. Clair County59.4-0.3 pts
27Clinton County59.4-0.4 pts
28Kankakee County59.2-0.2 pts
29Christian County59.2-0.2 pts
30Boone County59.10 pts
31Sangamon County59-0.2 pts
32LaSalle County58.8-0.4 pts
33Winnebago County58.7-0.3 pts
34Peoria County58.4-0.3 pts
35Montgomery County58.3+0.2 pts
36Fulton County58.1-0 pts
37Jersey County58.1-0.2 pts
38Ogle County58.1-0.1 pts
39Monroe County58-0.2 pts
40Williamson County57.9-0.3 pts
41Crawford County57.8-0.8 pts
42De Witt County57.8-0.5 pts
43Cass County57.8-0.3 pts
44Livingston County57.8-0.2 pts
45Carroll County57.7-0.1 pts
46Jefferson County57.50 pts
47Rock Island County57.5-0.4 pts
48Knox County57.4-0.3 pts
49Warren County57.4-0.1 pts
50Tazewell County57.4-0.1 pts
51Putnam County57.4-0.7 pts
52Macoupin County57.2-0.3 pts
53Schuyler County57-1.2 pts
54Effingham County57-0.4 pts
55Washington County56.8-0.6 pts
56Adams County56.7-0.3 pts
57Menard County56.7-0.4 pts
58Macon County56.6-0.6 pts
59Union County56.5-0.3 pts
60Vermilion County56.5-0.2 pts
61Franklin County56.50 pts
62Bureau County56.4-0 pts
62Mason County56.4+0.1 pts
64Douglas County56.3-0.1 pts
65Mercer County56.3+0.2 pts
66Piatt County56.3-0.3 pts
67Massac County56.20 pts
68Woodford County56.1-0.1 pts
69Clark County56.1-0.3 pts
70Cumberland County56-0.4 pts
71Scott County56-0.2 pts
72Ford County55.9-0.4 pts
73Saline County55.8-0 pts
74Greene County55.8-0.3 pts
75Whiteside County55.8-0.2 pts
76Pulaski County55.7-0.8 pts
77Wabash County55.7-0.4 pts
78Henry County55.7-0.3 pts
79Edgar County55.6-0.6 pts
80Clay County55.5-0.2 pts
81Jasper County55.5-0.5 pts
82Marshall County55.5+0.1 pts
83Richland County55.4-0.3 pts
84Marion County55.4-0.3 pts
85Hamilton County55.4-0.2 pts
86Iroquois County55.4-0.1 pts
87Alexander County55.1-0.8 pts
88White County55-0.1 pts
89Edwards County55-0.3 pts
90Gallatin County54.9-0.1 pts
91Stark County54.9-0.3 pts
92Shelby County54.8-0.5 pts
93Wayne County54.8-0.1 pts
94Stephenson County54.6-0.4 pts
95Moultrie County54.4-0.2 pts
96Pope County54.3-0.9 pts
97Hancock County54.2-0.5 pts
98Henderson County54.1-0.8 pts
99Pike County54-0.2 pts
100Calhoun County53.9-0.6 pts
101Jo Daviess County52.7-0.1 pts
102Hardin County52.2-0.4 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.

Citation styles

The publisher is the author. Invokely is named only as the place the figures were read, where a style asks for it.

APA 7

U.S. Census Bureau. (2026). 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 (Counties in Illinois by population aged 18 to 64, 2021) [Data set]. Retrieved October 12, 2026, from https://www.census.gov/programs-surveys/popest/data/data-sets.html

MLA 9

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, Counties in Illinois by population aged 18 to 64, 2021. U.S. Census Bureau, 25 June 2026, https://www.census.gov/programs-surveys/popest/data/data-sets.html. Invokely, https://invokely.ai/rankings/population-18-64/illinois-counties?period=2021. Accessed 12 Oct. 2026.

Chicago (author-date)

U.S. Census Bureau. 2026. 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. Counties in Illinois by population aged 18 to 64, 2021. Dataset. Accessed October 12, 2026. https://www.census.gov/programs-surveys/popest/data/data-sets.html. Also distributed by Invokely, https://invokely.ai/rankings/population-18-64/illinois-counties?period=2021.

Harvard

U.S. Census Bureau (2026) 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, Counties in Illinois by population aged 18 to 64, 2021 [Dataset]. Available at: https://www.census.gov/programs-surveys/popest/data/data-sets.html, via Invokely: https://invokely.ai/rankings/population-18-64/illinois-counties?period=2021 (Accessed: 12 October 2026).

BibTeX
@misc{census_counties_in_illinois_by_2021,
  author = {{U.S. Census Bureau}},
  title = {{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: Counties in Illinois by population aged 18 to 64, 2021}},
  year = {2026},
  howpublished = {Data set},
  url = {https://www.census.gov/programs-surveys/popest/data/data-sets.html},
  urldate = {2026-10-12},
  note = {Accessed via Invokely, https://invokely.ai/rankings/population-18-64/illinois-counties?period=2021. Publisher attribution: 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.},
}
RIS
TY  - DATA
AU  - U.S. Census Bureau
TI  - 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: Counties in Illinois by population aged 18 to 64, 2021
PY  - 2026
DA  - 2026/06/25
PB  - U.S. Census Bureau
DB  - Invokely
UR  - https://www.census.gov/programs-surveys/popest/data/data-sets.html
L2  - https://invokely.ai/rankings/population-18-64/illinois-counties?period=2021
Y2  - 2026/10/12
N1  - Accessed via Invokely, https://invokely.ai/rankings/population-18-64/illinois-counties?period=2021.
N1  - Publisher attribution: 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.
ER  -
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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 67.1% in 2021, according to the U.S. Census Bureau.

Which county has the lowest population aged 18 to 64?

Hardin County, with 52.2% in 2021.

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