Data / Rankings / Population aged 65 and over / Counties in Illinois

Counties in Illinois by share of population aged 65 and over

Hardin County had the highest share of population aged 65 and over of 102 counties in 2020, at 29.7%. Kendall County had the lowest, at 11%. The median was 20.8% and the figure for Illinois was 16.4%. Source: the U.S. Census Bureau.

Highest29.7Hardin County
Lowest11Kendall County
Median20.8102 counties
Illinois16.4History

Top 40 counties, 2020

CSVChart (SVG)

Hardin CountyHardin County: 29.7 %29.7Jo Daviess CountyJo Daviess County: 28.3 %28.3Pope CountyPope County: 28.1 %28.1Henderson CountyHenderson County: 26.2 %26.2Calhoun CountyCalhoun County: 25.5 %25.5Gallatin CountyGallatin County: 25.2 %25.2Alexander CountyAlexander County: 24.9 %24.9Carroll CountyCarroll County: 24.2 %24.2Hancock CountyHancock County: 24.1 %24.1Marshall CountyMarshall County: 24.1 %24.1White CountyWhite County: 24 %24Schuyler CountySchuyler County: 23.9 %23.9Stephenson CountyStephenson County: 23.8 %23.8Mason CountyMason County: 23.4 %23.4Edgar CountyEdgar County: 23.4 %23.4Stark CountyStark County: 23.4 %23.4Shelby CountyShelby County: 23.3 %23.3Union CountyUnion County: 22.8 %22.8Pike CountyPike County: 22.8 %22.8Scott CountyScott County: 22.7 %22.7Putnam CountyPutnam County: 22.7 %22.7Pulaski CountyPulaski County: 22.6 %22.6Mercer CountyMercer County: 22.5 %22.5Bureau CountyBureau County: 22.5 %22.5Iroquois CountyIroquois County: 22.5 %22.5Knox CountyKnox County: 22.3 %22.3Whiteside CountyWhiteside County: 22.2 %22.2Fulton CountyFulton County: 22.2 %22.2Saline CountySaline County: 22 %22Hamilton CountyHamilton County: 22 %22Wayne CountyWayne County: 21.9 %21.9Franklin CountyFranklin County: 21.9 %21.9Edwards CountyEdwards County: 21.9 %21.9Wabash CountyWabash County: 21.9 %21.9Richland CountyRichland County: 21.7 %21.7Macoupin CountyMacoupin County: 21.7 %21.7Greene CountyGreene County: 21.7 %21.7Henry CountyHenry County: 21.6 %21.6Massac CountyMassac County: 21.6 %21.6Jasper CountyJasper County: 21.5 %21.5
%. Source: Invokely calculation with data from U.S. Census Bureau. Retrieved 2026-10-09.

Full ranking

RankCounties2020 (%)
1Hardin County29.7
2Jo Daviess County28.3
3Pope County28.1
4Henderson County26.2
5Calhoun County25.5
6Gallatin County25.2
7Alexander County24.9
8Carroll County24.2
9Hancock County24.1
10Marshall County24.1
11White County24
12Schuyler County23.9
13Stephenson County23.8
14Mason County23.4
15Edgar County23.4
16Stark County23.4
17Shelby County23.3
18Union County22.8
19Pike County22.8
20Scott County22.7
21Putnam County22.7
22Pulaski County22.6
23Mercer County22.5
24Bureau County22.5
25Iroquois County22.5
26Knox County22.3
27Whiteside County22.2
28Fulton County22.2
29Saline County22
30Hamilton County22
31Wayne County21.9
32Franklin County21.9
33Edwards County21.9
34Wabash County21.9
35Richland County21.7
36Macoupin County21.7
37Greene County21.7
38Henry County21.6
39Massac County21.6
40Jasper County21.5
41Montgomery County21.5
42Washington County21.4
43Clay County21.4
44Marion County21.3
45Clark County21.3
46Ford County21.3
47Crawford County21.2
48Piatt County21.2
49Jersey County21.2
50Moultrie County21.2
51Cumberland County20.8
52Warren County20.8
53Christian County20.8
54Adams County20.6
55Perry County20.6
56Morgan County20.6
57Macon County20.6
58Menard County20.4
59Randolph County20.3
60Jefferson County20.3
60Vermilion County20.3
62De Witt County20.2
63Livingston County20.2
64Johnson County20.2
65Williamson County20.1
66Lee County20.1
67Tazewell County20
68Logan County19.9
69McDonough County19.9
70Rock Island County19.9
71LaSalle County19.8
72Woodford County19.6
73Lawrence County19.4
74Effingham County19.3
75Ogle County19.2
76Monroe County19
77Coles County19
78Douglas County18.9
79Sangamon County18.8
80Bond County18.7
81Fayette County18.6
82Clinton County18.3
83Madison County18.2
84Winnebago County18
85Peoria County17.9
86Kankakee County17.8
87Cass County17.3
88Jackson County17.2
89St. Clair County16.7
90DuPage County16.6
91Boone County16.4
92Brown County16
93McHenry County15.7
94Grundy County15.3
95Lake County15.1
96Cook County15.1
97Kane County14.7
98McLean County14.5
99DeKalb County14.4
100Will County14.2
101Champaign County13.4
102Kendall County11

Other periods

About this ranking

Residents aged 65 or over as a percentage of total population. Spain: 1 January, INE annual census. United States: 1 July, Census Bureau population estimates. World Bank figures for other countries and the World refer to mid-year.

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 (cc-est agesex): residents aged 65 and over as a percentage of the total, 1 July; states and the nation summed from counties. https://www2.census.gov/programs-surveys/popest/datasets/2020-2025/counties/asrh/cc-est2025-agesex-all.csv. Retrieved 2026-10-09.

Use this data in your AI agent

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Rank Counties in Illinois by share of population aged 65 and over using official data, and cite the source.
rank_places {"indicator":"population_65_plus_share","level":"province","within":"Illinois","limit":10}
GET https://invokely.ai/api/v1/rank?indicator=population_65_plus_share&level=province&within=Illinois&limit=10

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Questions

Which county has the highest share of population aged 65 and over?

Hardin County, with 29.7% in 2020, according to the U.S. Census Bureau.

Which county has the lowest share of population aged 65 and over?

Kendall County, with 11% in 2020.

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 (cc-est agesex): residents aged 65 and over as a percentage of the total, 1 July; states and the nation summed from counties. Retrieved 2026-10-09.

Population aged 65 and over: other rankings

Counties in Illinois: more rankings