Data / Rankings / Median age / Counties in Illinois

Counties in Illinois by median age

Hardin County had the highest median age of 102 counties in 2021, at 53.3 years. Champaign County had the lowest, at 30.6 years. The median was 42.1 years and the figure for Illinois was 38.5 years. Source: the U.S. Census Bureau.

Highest53.3Hardin County
Lowest30.6Champaign County
Median42.1102 counties
Illinois38.5History

Top 40 counties, 2021

CSVChart (SVG)

Hardin CountyHardin County: 53.3 years53.3Jo Daviess CountyJo Daviess County: 50.5 years50.5Henderson CountyHenderson County: 50.1 years50.1Pope CountyPope County: 49.8 years49.8Calhoun CountyCalhoun County: 48.3 years48.3Schuyler CountySchuyler County: 47.8 years47.8Carroll CountyCarroll County: 47.3 years47.3Putnam CountyPutnam County: 46.9 years46.9Gallatin CountyGallatin County: 46.7 years46.7Marshall CountyMarshall County: 46.5 years46.5Hancock CountyHancock County: 45.8 years45.8Edgar CountyEdgar County: 45.7 years45.7Stephenson CountyStephenson County: 45.6 years45.6Alexander CountyAlexander County: 45.5 years45.5Stark CountyStark County: 45.3 years45.3Mason CountyMason County: 45.2 years45.2Shelby CountyShelby County: 45 years45Mercer CountyMercer County: 44.6 years44.6Scott CountyScott County: 44.6 years44.6Edwards CountyEdwards County: 44.3 years44.3De Witt CountyDe Witt County: 44.2 years44.2Iroquois CountyIroquois County: 44.2 years44.2Pulaski CountyPulaski County: 44.2 years44.2Washington CountyWashington County: 44.2 years44.2Jasper CountyJasper County: 44.1 years44.1White CountyWhite County: 44.1 years44.1Wabash CountyWabash County: 44 years44Bureau CountyBureau County: 43.9 years43.9Hamilton CountyHamilton County: 43.9 years43.9Union CountyUnion County: 43.8 years43.8Macoupin CountyMacoupin County: 43.7 years43.7Massac CountyMassac County: 43.7 years43.7Fulton CountyFulton County: 43.6 years43.6Whiteside CountyWhiteside County: 43.6 years43.6Henry CountyHenry County: 43.5 years43.5Johnson CountyJohnson County: 43.4 years43.4Menard CountyMenard County: 43.4 years43.4Franklin CountyFranklin County: 43.2 years43.2Wayne CountyWayne County: 43.2 years43.2Jersey CountyJersey County: 43 years43
years. Source: U.S. Census Bureau. Retrieved 2026-10-08.

Full ranking

RankCounties2021
years
1Hardin County53.3
2Jo Daviess County50.5
3Henderson County50.1
4Pope County49.8
5Calhoun County48.3
6Schuyler County47.8
7Carroll County47.3
8Putnam County46.9
9Gallatin County46.7
10Marshall County46.5
11Hancock County45.8
12Edgar County45.7
13Stephenson County45.6
14Alexander County45.5
15Stark County45.3
16Mason County45.2
17Shelby County45
18Mercer County44.6
18Scott County44.6
20Edwards County44.3
21De Witt County44.2
21Iroquois County44.2
21Pulaski County44.2
21Washington County44.2
25Jasper County44.1
25White County44.1
27Wabash County44
28Bureau County43.9
28Hamilton County43.9
30Union County43.8
31Macoupin County43.7
31Massac County43.7
33Fulton County43.6
33Whiteside County43.6
35Henry County43.5
36Johnson County43.4
36Menard County43.4
38Franklin County43.2
38Wayne County43.2
40Jersey County43
41Lee County42.8
41Montgomery County42.8
43Christian County42.6
43Ford County42.6
45Cumberland County42.5
46Monroe County42.3
46Ogle County42.3
46Richland County42.3
49Crawford County42.2
50Clay County42.1
50Fayette County42.1
50Marion County42.1
53Greene County42
54Piatt County41.9
54Randolph County41.9
56Clark County41.8
56Knox County41.8
56LaSalle County41.8
59Saline County41.7
60Livingston County41.6
61Bond County41.5
61Perry County41.5
63Tazewell County41.4
64Adams County41.2
64Clinton County41.2
64Jefferson County41.2
67Pike County41.1
67Williamson County41.1
69Morgan County40.9
70Lawrence County40.8
70Macon County40.8
72Vermilion County40.6
73Moultrie County40.5
73Sangamon County40.5
75McHenry County40.4
76Madison County40.2
77Rock Island County40.1
78Woodford County40
79Logan County39.9
80DuPage County39.7
81Warren County39.6
81Winnebago County39.6
83Effingham County39.2
83St. Clair County39.2
85Boone County38.8
86Kankakee County38.5
86Lake County38.5
88Douglas County38.4
89Cass County38.3
89Grundy County38.3
89Will County38.3
92Brown County38.1
93Kane County38
94Peoria County37.8
95Cook County37.3
96Coles County36.6
97Kendall County35.8
98McDonough County33.7
99McLean County33.6
100Jackson County32.4
101DeKalb County31.4
102Champaign County30.6

Other periods

About this ranking

Age that divides the resident population into two halves of equal size. Spain and the EU: on 1 January. United States: American Community Survey five-year estimate, where the period shown is the last year of the five-year span.

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. American Community Survey 5-year estimates, table B01002: median age, total population. https://www2.census.gov/programs-surveys/acs/summary_file/2021/table-based-SF/data/5YRData/acsdt5y2021-b01002.dat. Retrieved 2026-10-08.

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Questions

Which county has the highest median age?

Hardin County, with 53.3 years in 2021, according to the U.S. Census Bureau.

Which county has the lowest median age?

Champaign County, with 30.6 years 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, American Community Survey 5-year estimates, table B01002: median age, total population. Retrieved 2026-10-08.

Median age: other rankings

Counties in Illinois: more rankings