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 2019, at 67.7%. Jo Daviess County had the lowest, at 53.3%. The median was 58.1% and the figure for Illinois was 61.9%. Source: the U.S. Census Bureau.

Highest67.7Champaign County
Lowest53.3Jo Daviess County
Median58.1102 counties
Illinois61.9History

Top 40 counties, 2019

Champaign County: 67.7 %Champaign County67.7Brown County: 67.7 %Brown County67.7McLean County: 64.2 %McLean County64.2Cook County: 64.2 %Cook County64.2Jackson County: 64.1 %Jackson County64.1DeKalb County: 63.7 %DeKalb County63.7Bond County: 63.1 %Bond County63.1Johnson County: 62.7 %Johnson County62.7McDonough County: 62.3 %McDonough County62.3Coles County: 62.1 %Coles County62.1Lawrence County: 62 %Lawrence County62McHenry County: 61.7 %McHenry County61.7Will County: 61.6 %Will County61.6DuPage County: 61.5 %DuPage County61.5Lake County: 61.4 %Lake County61.4Fayette County: 61.1 %Fayette County61.1Logan County: 61 %Logan County61Madison County: 60.9 %Madison County60.9Kane County: 60.8 %Kane County60.8Lee County: 60.7 %Lee County60.7Perry County: 60.6 %Perry County60.6Clinton County: 60.5 %Clinton County60.5Kendall County: 60.4 %Kendall County60.4Randolph County: 60.4 %Randolph County60.4St. Clair County: 60.3 %St. Clair County60.3Grundy County: 60.1 %Grundy County60.1Christian County: 59.8 %Christian County59.8Kankakee County: 59.7 %Kankakee County59.7Sangamon County: 59.7 %Sangamon County59.7Morgan County: 59.6 %Morgan County59.6LaSalle County: 59.5 %LaSalle County59.5Winnebago County: 59.4 %Winnebago County59.4Peoria County: 59.3 %Peoria County59.3Crawford County: 59.2 %Crawford County59.2Monroe County: 59.1 %Monroe County59.1Boone County: 59 %Boone County59Montgomery County: 58.9 %Montgomery County58.9Jersey County: 58.8 %Jersey County58.8De Witt County: 58.7 %De Witt County58.7Fulton County: 58.6 %Fulton County58.6
%. Source: Invokely calculation with data from U.S. Census Bureau. Retrieved 2026-10-12.

Full ranking

RankCounties2019 (%)Change on 2018
1Champaign County67.7-0.5 pts
2Brown County67.7-0.5 pts
3McLean County64.2-0.4 pts
4Cook County64.2-0.1 pts
5Jackson County64.1-0.8 pts
6DeKalb County63.7-0.5 pts
7Bond County63.1-0.1 pts
8Johnson County62.7+0.2 pts
9McDonough County62.3-0.8 pts
10Coles County62.1-0.7 pts
11Lawrence County62-0.6 pts
12McHenry County61.7-0.3 pts
13Will County61.6-0.1 pts
14DuPage County61.5-0.4 pts
15Lake County61.4-0.3 pts
16Fayette County61.1+0.2 pts
17Logan County61-0.4 pts
18Madison County60.9-0.3 pts
19Kane County60.8-0 pts
20Lee County60.7-0.3 pts
21Perry County60.6-0.7 pts
22Clinton County60.5-0.5 pts
23Kendall County60.4-0.2 pts
24Randolph County60.4-0.4 pts
25St. Clair County60.3-0.5 pts
26Grundy County60.1-0.2 pts
27Christian County59.8-0.2 pts
28Kankakee County59.7-0.3 pts
29Sangamon County59.7-0.3 pts
30Morgan County59.6-0.4 pts
31LaSalle County59.5-0.2 pts
32Winnebago County59.4-0.4 pts
33Peoria County59.3-0.4 pts
34Crawford County59.2-0.5 pts
35Monroe County59.1-0.6 pts
36Boone County59-0.1 pts
37Montgomery County58.9-0.4 pts
38Jersey County58.8-0.4 pts
39De Witt County58.7-0.2 pts
40Fulton County58.6-0.3 pts
41Livingston County58.5-0.2 pts
42Ogle County58.5-0.3 pts
43Williamson County58.5-0.4 pts
44Rock Island County58.4-0.4 pts
45Cass County58.4-0.3 pts
46Putnam County58.4-0.1 pts
47Scott County58.3+0.5 pts
48Knox County58.3-0.5 pts
49Schuyler County58.2-0.9 pts
50Effingham County58.1-0.6 pts
51Warren County58.1-0.2 pts
52Carroll County58-0.1 pts
53Macoupin County58-0.4 pts
54Washington County57.9-0.5 pts
55Jefferson County57.9-0.5 pts
56Macon County57.8-0.4 pts
57Tazewell County57.8-0.4 pts
58Menard County57.7-0.2 pts
59Union County57.6-0.3 pts
60Adams County57.4-0.3 pts
61Vermilion County57.3-0.3 pts
62Wabash County57.3-0.3 pts
63Piatt County57.3-0.2 pts
64Clark County57.1-0.1 pts
65Franklin County57.1-0.2 pts
66Cumberland County57-0.8 pts
67Ford County56.8-0.5 pts
68Bureau County56.8-0.2 pts
69Jasper County56.7-0.8 pts
70Pulaski County56.7-0.3 pts
71Edgar County56.7-0.6 pts
72Douglas County56.6+0.1 pts
73Whiteside County56.6-0.4 pts
74Mason County56.6-0.7 pts
75Greene County56.6-0.7 pts
76Marion County56.5-0.3 pts
77Woodford County56.4-0.4 pts
78Saline County56.4-0.5 pts
79Mercer County56.40 pts
80Massac County56.3-0 pts
81Richland County56.3-0.2 pts
82Clay County56.2-0.2 pts
83Henry County56.1-0.3 pts
84Shelby County56-0.5 pts
85Iroquois County56-0.5 pts
86Hamilton County55.9-0.1 pts
87Marshall County55.8-0.6 pts
88White County55.8-0.3 pts
89Henderson County55.8-0.7 pts
90Edwards County55.5-0.7 pts
91Hancock County55.5-0.4 pts
92Stephenson County55.4-0.5 pts
93Alexander County55.3-0.4 pts
94Pike County55.3-0.6 pts
95Wayne County55.3-0.3 pts
96Stark County55.2-0.4 pts
97Gallatin County54.7-0.5 pts
98Moultrie County54.5-0.5 pts
99Calhoun County54.4-0.5 pts
100Pope County54.1-1 pts
101Hardin County53.3-0.7 pts
102Jo Daviess County53.3-0.2 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, 2019) [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, 2019. 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=2019. 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, 2019. 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=2019.

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, 2019 [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=2019 (Accessed: 12 October 2026).

BibTeX
@misc{census_counties_in_illinois_by_2019,
  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, 2019}},
  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=2019. 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, 2019
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=2019
Y2  - 2026/10/12
N1  - Accessed via Invokely, https://invokely.ai/rankings/population-18-64/illinois-counties?period=2019.
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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Questions

Which county has the highest population aged 18 to 64?

Champaign County, with 67.7% in 2019, according to the U.S. Census Bureau.

Which county has the lowest population aged 18 to 64?

Jo Daviess County, with 53.3% in 2019.

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