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

Counties in Iowa by share of population aged 65 and over

Dickinson County had the highest share of population aged 65 and over of 99 counties in 2020, at 27.7%. Dallas County had the lowest, at 12.6%. The median was 21.6% and the figure for Iowa was 18.1%. Source: the U.S. Census Bureau.

Highest27.7Dickinson County
Lowest12.6Dallas County
Median21.699 counties
Iowa18.1History

Top 40 counties, 2020

CSVChart (SVG)

Dickinson CountyDickinson County: 27.7 %27.7Jefferson CountyJefferson County: 27.5 %27.5Ringgold CountyRinggold County: 26.2 %26.2Cherokee CountyCherokee County: 25.4 %25.4Audubon CountyAudubon County: 25.2 %25.2Monona CountyMonona County: 25 %25Kossuth CountyKossuth County: 24.7 %24.7Butler CountyButler County: 24.6 %24.6Sac CountySac County: 24.5 %24.5Clayton CountyClayton County: 24.5 %24.5Hancock CountyHancock County: 24.5 %24.5Cass CountyCass County: 24.2 %24.2Taylor CountyTaylor County: 24.2 %24.2Appanoose CountyAppanoose County: 24 %24Greene CountyGreene County: 24 %24Pocahontas CountyPocahontas County: 24 %24Guthrie CountyGuthrie County: 23.9 %23.9Emmet CountyEmmet County: 23.6 %23.6Adair CountyAdair County: 23.6 %23.6Palo Alto CountyPalo Alto County: 23.6 %23.6Hardin CountyHardin County: 23.5 %23.5Calhoun CountyCalhoun County: 23.5 %23.5Page CountyPage County: 23.5 %23.5Shelby CountyShelby County: 23.4 %23.4Cerro Gordo CountyCerro Gordo County: 23.4 %23.4Montgomery CountyMontgomery County: 23.3 %23.3Ida CountyIda County: 23.2 %23.2Van Buren CountyVan Buren County: 23.2 %23.2Mitchell CountyMitchell County: 23.1 %23.1Fremont CountyFremont County: 23 %23Adams CountyAdams County: 23 %23Allamakee CountyAllamakee County: 23 %23Fayette CountyFayette County: 22.9 %22.9Lee CountyLee County: 22.9 %22.9Winnebago CountyWinnebago County: 22.5 %22.5Floyd CountyFloyd County: 22.5 %22.5O'Brien CountyO'Brien County: 22.3 %22.3Worth CountyWorth County: 22.2 %22.2Jackson CountyJackson County: 22.2 %22.2Clay CountyClay County: 22.1 %22.1
%. Source: Invokely calculation with data from U.S. Census Bureau. Retrieved 2026-10-09.

Full ranking

RankCounties2020 (%)
1Dickinson County27.7
2Jefferson County27.5
3Ringgold County26.2
4Cherokee County25.4
5Audubon County25.2
6Monona County25
7Kossuth County24.7
8Butler County24.6
9Sac County24.5
10Clayton County24.5
11Hancock County24.5
12Cass County24.2
13Taylor County24.2
14Appanoose County24
15Greene County24
16Pocahontas County24
17Guthrie County23.9
18Emmet County23.6
19Adair County23.6
20Palo Alto County23.6
21Hardin County23.5
22Calhoun County23.5
23Page County23.5
24Shelby County23.4
25Cerro Gordo County23.4
26Montgomery County23.3
27Ida County23.2
28Van Buren County23.2
29Mitchell County23.1
30Fremont County23
31Adams County23
32Allamakee County23
33Fayette County22.9
34Lee County22.9
35Winnebago County22.5
36Floyd County22.5
37O'Brien County22.3
38Worth County22.2
39Jackson County22.2
40Clay County22.1
41Franklin County22.1
42Lucas County22.1
43Chickasaw County22
44Winneshiek County22
45Keokuk County22
46Wright County21.9
47Des Moines County21.8
48Grundy County21.7
49Poweshiek County21.6
50Monroe County21.6
51Carroll County21.6
52Howard County21.4
53Osceola County21.3
54Humboldt County21.3
55Union County21.3
56Hamilton County21.2
57Wayne County21.1
58Jones County21.1
59Harrison County20.9
60Washington County20.8
61Decatur County20.7
62Tama County20.7
63Delaware County20.6
64Cedar County20.6
65Bremer County20.3
66Clinton County20.3
67Boone County20.3
68Clarke County20
69Iowa County19.9
70Henry County19.9
71Louisa County19.9
72Webster County19.8
73Marion County19.7
74Mills County19.5
75Jasper County19.5
76Marshall County19.3
77Mahaska County19.2
78Plymouth County19.1
79Dubuque County19
80Buchanan County18.8
81Wapello County18.7
82Lyon County18.6
83Benton County18.6
84Madison County18.2
85Pottawattamie County18.2
86Crawford County18.1
87Muscatine County18
88Black Hawk County17.8
89Davis County17.7
90Scott County17.2
91Warren County17.1
92Linn County16.6
93Buena Vista County16.2
94Sioux County15.8
95Woodbury County15.4
96Polk County14.1
97Story County13.2
98Johnson County12.8
99Dallas County12.6

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.

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Rank Counties in Iowa 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":"Iowa","limit":10}
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Questions

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

Dickinson County, with 27.7% in 2020, according to the U.S. Census Bureau.

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

Dallas County, with 12.6% 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 Iowa: more rankings