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 2021, at 30%. Kendall County had the lowest, at 11.2%. The median was 21.2% and the figure for Illinois was 16.9%. Source: the U.S. Census Bureau.

Highest30Hardin County
Lowest11.2Kendall County
Median21.2102 counties
Illinois16.9History

Top 40 counties, 2021

CSVChart (SVG)

Hardin CountyHardin County: 30 %30Pope CountyPope County: 29.2 %29.2Jo Daviess CountyJo Daviess County: 28.9 %28.9Henderson CountyHenderson County: 26.7 %26.7Calhoun CountyCalhoun County: 25.9 %25.9Gallatin CountyGallatin County: 25.8 %25.8Alexander CountyAlexander County: 25.2 %25.2Schuyler CountySchuyler County: 24.9 %24.9Hancock CountyHancock County: 24.6 %24.6Carroll CountyCarroll County: 24.5 %24.5Stephenson CountyStephenson County: 24.3 %24.3Marshall CountyMarshall County: 24.3 %24.3Edgar CountyEdgar County: 24 %24White CountyWhite County: 23.9 %23.9Stark CountyStark County: 23.8 %23.8Shelby CountyShelby County: 23.8 %23.8Scott CountyScott County: 23.6 %23.6Mason CountyMason County: 23.6 %23.6Pulaski CountyPulaski County: 23.5 %23.5Putnam CountyPutnam County: 23.5 %23.5Union CountyUnion County: 23.4 %23.4Iroquois CountyIroquois County: 23 %23Bureau CountyBureau County: 22.9 %22.9Edwards CountyEdwards County: 22.9 %22.9Pike CountyPike County: 22.7 %22.7Knox CountyKnox County: 22.6 %22.6Wabash CountyWabash County: 22.6 %22.6Fulton CountyFulton County: 22.6 %22.6Whiteside CountyWhiteside County: 22.5 %22.5Mercer CountyMercer County: 22.5 %22.5Saline CountySaline County: 22.3 %22.3Hamilton CountyHamilton County: 22.2 %22.2Washington CountyWashington County: 22.2 %22.2Wayne CountyWayne County: 22.2 %22.2Macoupin CountyMacoupin County: 22.2 %22.2Franklin CountyFranklin County: 22.1 %22.1Massac CountyMassac County: 22.1 %22.1Henry CountyHenry County: 22 %22Greene CountyGreene County: 22 %22Jasper CountyJasper County: 21.9 %21.9
%. Source: Invokely calculation with data from U.S. Census Bureau. Retrieved 2026-10-09.

Full ranking

RankCounties2021 (%)Change on 2020
1Hardin County30+0.3 pts
2Pope County29.2+1.1 pts
3Jo Daviess County28.9+0.6 pts
4Henderson County26.7+0.5 pts
5Calhoun County25.9+0.4 pts
6Gallatin County25.8+0.6 pts
7Alexander County25.2+0.2 pts
8Schuyler County24.9+1 pts
9Hancock County24.6+0.5 pts
10Carroll County24.5+0.3 pts
11Stephenson County24.3+0.6 pts
12Marshall County24.3+0.2 pts
13Edgar County24+0.7 pts
14White County23.9-0.1 pts
15Stark County23.8+0.5 pts
16Shelby County23.8+0.5 pts
17Scott County23.6+0.9 pts
18Mason County23.6+0.2 pts
19Pulaski County23.5+0.9 pts
20Putnam County23.5+0.8 pts
21Union County23.4+0.6 pts
22Iroquois County23+0.5 pts
23Bureau County22.9+0.4 pts
24Edwards County22.9+0.9 pts
25Pike County22.7-0.1 pts
26Knox County22.6+0.4 pts
27Wabash County22.6+0.7 pts
28Fulton County22.6+0.3 pts
29Whiteside County22.5+0.3 pts
30Mercer County22.5-0 pts
31Saline County22.3+0.3 pts
32Hamilton County22.2+0.3 pts
33Washington County22.2+0.8 pts
34Wayne County22.2+0.3 pts
35Macoupin County22.2+0.5 pts
36Franklin County22.1+0.2 pts
37Massac County22.1+0.5 pts
38Henry County22+0.4 pts
39Greene County22+0.3 pts
40Jasper County21.9+0.5 pts
41Richland County21.9+0.2 pts
42Crawford County21.8+0.5 pts
43Jersey County21.7+0.5 pts
44Clay County21.7+0.3 pts
45Piatt County21.7+0.4 pts
46Montgomery County21.5+0.1 pts
47Cumberland County21.5+0.7 pts
48Ford County21.5+0.2 pts
49Clark County21.4+0.2 pts
50Marion County21.4+0.1 pts
51Christian County21.2+0.4 pts
52Menard County21.2+0.8 pts
53Moultrie County21.2-0 pts
54Macon County21.1+0.6 pts
55Perry County21.1+0.5 pts
56Adams County21+0.4 pts
57Warren County20.9+0.1 pts
58Morgan County20.9+0.3 pts
59De Witt County20.8+0.5 pts
60Williamson County20.6+0.4 pts
61Vermilion County20.6+0.3 pts
62Randolph County20.5+0.2 pts
63Logan County20.5+0.5 pts
64Livingston County20.5+0.3 pts
65Lee County20.5+0.3 pts
66Jefferson County20.5+0.2 pts
67Rock Island County20.4+0.5 pts
68Tazewell County20.3+0.3 pts
69LaSalle County20.3+0.4 pts
70Johnson County20.2-0 pts
71Woodford County20.1+0.5 pts
72McDonough County20+0.1 pts
73Effingham County19.7+0.4 pts
74Lawrence County19.7+0.3 pts
75Ogle County19.6+0.4 pts
76Monroe County19.6+0.6 pts
77Sangamon County19.3+0.4 pts
78Fayette County19.2+0.7 pts
79Bond County19.2+0.4 pts
80Douglas County19.1+0.2 pts
81Coles County19+0.1 pts
82Clinton County18.9+0.6 pts
83Madison County18.6+0.4 pts
84Winnebago County18.4+0.4 pts
85Peoria County18.3+0.4 pts
86Kankakee County18.3+0.4 pts
87Cass County17.7+0.4 pts
88Jackson County17.5+0.3 pts
89DuPage County17.2+0.6 pts
90St. Clair County17.1+0.5 pts
91Boone County16.8+0.4 pts
92McHenry County16.2+0.5 pts
93Brown County15.9-0.1 pts
94Cook County15.6+0.6 pts
95Lake County15.6+0.5 pts
96Grundy County15.5+0.2 pts
97Kane County15.2+0.5 pts
98McLean County14.9+0.4 pts
99DeKalb County14.7+0.3 pts
100Will County14.6+0.4 pts
101Champaign County13.7+0.4 pts
102Kendall County11.2+0.2 pts

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 30% in 2021, according to the U.S. Census Bureau.

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

Kendall County, with 11.2% 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 (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