Counties in Iowa by median age on 1 July (US county estimates)

Dickinson County had the highest median age on 1 July (US county estimates) of 99 counties in 2023, at 49.5 years. Story County had the lowest, at 26.4 years. The median was 42.9 years. Source: the U.S. Census Bureau.

Keep it in a collection in your library.
Highest49.5Dickinson County
Lowest26.4Story County
Median42.999 counties

Map of counties, 2023

Adair County: 43.6 yearsAdams County: 46.8 yearsAllamakee County: 43 yearsAppanoose County: 45.4 yearsAudubon County: 46.3 yearsBenton County: 42.5 yearsBlack Hawk County: 36.6 yearsBoone County: 42.5 yearsBremer County: 40 yearsBuchanan County: 40.3 yearsBuena Vista County: 36.1 yearsButler County: 45.4 yearsCalhoun County: 43.7 yearsCarroll County: 42.2 yearsCass County: 44.5 yearsCedar County: 44.1 yearsCerro Gordo County: 44.9 yearsCherokee County: 44.8 yearsChickasaw County: 44 yearsClarke County: 40.5 yearsClay County: 42.8 yearsClayton County: 46.2 yearsClinton County: 42.7 yearsCrawford County: 38.1 yearsDallas County: 36.3 yearsDavis County: 36.1 yearsDecatur County: 37.2 yearsDelaware County: 43.6 yearsDes Moines County: 43 yearsDickinson County: 49.5 yearsDubuque County: 39.6 yearsEmmet County: 42.9 yearsFayette County: 44 yearsFloyd County: 42.9 yearsFranklin County: 42.6 yearsFremont County: 45.9 yearsGreene County: 45.2 yearsGrundy County: 42.4 yearsGuthrie County: 46.4 yearsHamilton County: 42.4 yearsHancock County: 45.1 yearsHardin County: 43.8 yearsHarrison County: 43.4 yearsHenry County: 42.2 yearsHoward County: 42.2 yearsHumboldt County: 41.9 yearsIda County: 43.2 yearsIowa County: 43.2 yearsJackson County: 45.1 yearsJasper County: 42.1 yearsJefferson County: 45.8 yearsJohnson County: 31.9 yearsJones County: 43.9 yearsKeokuk County: 43.4 yearsKossuth County: 45.5 yearsLee County: 44.2 yearsLinn County: 39 yearsLouisa County: 43.5 yearsLucas County: 43.1 yearsLyon County: 37.4 yearsMadison County: 41.9 yearsMahaska County: 39.7 yearsMarion County: 41.2 yearsMarshall County: 38.6 yearsMills County: 42.9 yearsMitchell County: 43.4 yearsMonona County: 44.7 yearsMonroe County: 43.1 yearsMontgomery County: 44.4 yearsMuscatine County: 40.8 yearsO'Brien County: 40.5 yearsOsceola County: 44 yearsPage County: 43.7 yearsPalo Alto County: 43.3 yearsPlymouth County: 41.3 yearsPocahontas County: 44.6 yearsPolk County: 36.5 yearsPottawattamie County: 40.7 yearsPoweshiek County: 41.1 yearsRinggold County: 45.6 yearsSac County: 45.4 yearsScott County: 39.7 yearsShelby County: 44.9 yearsSioux County: 33.6 yearsStory County: 26.4 yearsTama County: 42.2 yearsTaylor County: 42.5 yearsUnion County: 41.6 yearsVan Buren County: 43.5 yearsWapello County: 39.1 yearsWarren County: 38.8 yearsWashington County: 41.2 yearsWayne County: 40 yearsWebster County: 39.9 yearsWinnebago County: 43.1 yearsWinneshiek County: 43.8 yearsWoodbury County: 36 yearsWorth County: 43.9 yearsWright County: 40.2 years
  • Under 40
  • 40 to 42
  • 42 to 43
  • 43 to 44
  • 44 to 45
  • 45 and over
years, 2023. Source: U.S. Census Bureau, Population Estimates Program, county population by age and sex: median age (MEDIAN_AGE_TOT) on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage. Boundaries: U.S. Census Bureau cartographic boundary files.

Top 40 counties, 2023

Dickinson County: 49.5 yearsDickinson County49.5Adams County: 46.8 yearsAdams County46.8Guthrie County: 46.4 yearsGuthrie County46.4Audubon County: 46.3 yearsAudubon County46.3Clayton County: 46.2 yearsClayton County46.2Fremont County: 45.9 yearsFremont County45.9Jefferson County: 45.8 yearsJefferson County45.8Ringgold County: 45.6 yearsRinggold County45.6Kossuth County: 45.5 yearsKossuth County45.5Appanoose County: 45.4 yearsAppanoose County45.4Butler County: 45.4 yearsButler County45.4Sac County: 45.4 yearsSac County45.4Greene County: 45.2 yearsGreene County45.2Hancock County: 45.1 yearsHancock County45.1Jackson County: 45.1 yearsJackson County45.1Cerro Gordo County: 44.9 yearsCerro Gordo County44.9Shelby County: 44.9 yearsShelby County44.9Cherokee County: 44.8 yearsCherokee County44.8Monona County: 44.7 yearsMonona County44.7Pocahontas County: 44.6 yearsPocahontas County44.6Cass County: 44.5 yearsCass County44.5Montgomery County: 44.4 yearsMontgomery County44.4Lee County: 44.2 yearsLee County44.2Cedar County: 44.1 yearsCedar County44.1Chickasaw County: 44 yearsChickasaw County44Fayette County: 44 yearsFayette County44Osceola County: 44 yearsOsceola County44Jones County: 43.9 yearsJones County43.9Worth County: 43.9 yearsWorth County43.9Hardin County: 43.8 yearsHardin County43.8Winneshiek County: 43.8 yearsWinneshiek County43.8Calhoun County: 43.7 yearsCalhoun County43.7Page County: 43.7 yearsPage County43.7Adair County: 43.6 yearsAdair County43.6Delaware County: 43.6 yearsDelaware County43.6Louisa County: 43.5 yearsLouisa County43.5Van Buren County: 43.5 yearsVan Buren County43.5Harrison County: 43.4 yearsHarrison County43.4Keokuk County: 43.4 yearsKeokuk County43.4Mitchell County: 43.4 yearsMitchell County43.4Dickinson County: 49.5 yearsDickinson County49.5Adams County: 46.8 yearsAdams County46.8Guthrie County: 46.4 yearsGuthrie County46.4Audubon County: 46.3 yearsAudubon County46.3Clayton County: 46.2 yearsClayton County46.2Fremont County: 45.9 yearsFremont County45.9Jefferson County: 45.8 yearsJefferson County45.8Ringgold County: 45.6 yearsRinggold County45.6Kossuth County: 45.5 yearsKossuth County45.5Appanoose County: 45.4 yearsAppanoose County45.4Butler County: 45.4 yearsButler County45.4Sac County: 45.4 yearsSac County45.4Greene County: 45.2 yearsGreene County45.2Hancock County: 45.1 yearsHancock County45.1Jackson County: 45.1 yearsJackson County45.1Cerro Gordo County: 44.9 yearsCerro Gordo County44.9Shelby County: 44.9 yearsShelby County44.9Cherokee County: 44.8 yearsCherokee County44.8Monona County: 44.7 yearsMonona County44.7Pocahontas County: 44.6 yearsPocahontas County44.6Cass County: 44.5 yearsCass County44.5Montgomery County: 44.4 yearsMontgomery County44.4Lee County: 44.2 yearsLee County44.2Cedar County: 44.1 yearsCedar County44.1Chickasaw County: 44 yearsChickasaw County44Fayette County: 44 yearsFayette County44Osceola County: 44 yearsOsceola County44Jones County: 43.9 yearsJones County43.9Worth County: 43.9 yearsWorth County43.9Hardin County: 43.8 yearsHardin County43.8Winneshiek County: 43.8 yearsWinneshiek County43.8Calhoun County: 43.7 yearsCalhoun County43.7Page County: 43.7 yearsPage County43.7Adair County: 43.6 yearsAdair County43.6Delaware County: 43.6 yearsDelaware County43.6Louisa County: 43.5 yearsLouisa County43.5Van Buren County: 43.5 yearsVan Buren County43.5Harrison County: 43.4 yearsHarrison County43.4Keokuk County: 43.4 yearsKeokuk County43.4Mitchell County: 43.4 yearsMitchell County43.4
years. Source: U.S. Census Bureau, Population Estimates Program, county population by age and sex: median age (MEDIAN_AGE_TOT) on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage. Retrieved 2026-10-12.

Full ranking

RankCounties2023
years
Change on 2022
1Dickinson County49.5+0.2
2Adams County46.8+0.5
3Guthrie County46.4-0.1
4Audubon County46.30
5Clayton County46.2+0.2
6Fremont County45.9+0.3
7Jefferson County45.80
8Ringgold County45.6+0.7
9Kossuth County45.5-0.2
10Appanoose County45.4+0.1
10Butler County45.4+0.1
10Sac County45.4-0.2
13Greene County45.2+0.6
14Hancock County45.1-0.2
14Jackson County45.1-0.1
16Cerro Gordo County44.90
16Shelby County44.9-0.9
18Cherokee County44.8-0.8
19Monona County44.7-0.5
20Pocahontas County44.60
21Cass County44.5-0.5
22Montgomery County44.4+0.1
23Lee County44.20
24Cedar County44.1+0.4
25Chickasaw County440
25Fayette County44+0.1
25Osceola County44+0.6
28Jones County43.9+0.3
28Worth County43.90
30Hardin County43.8+0.3
30Winneshiek County43.8+0.5
32Calhoun County43.7-0.6
32Page County43.7+0.1
34Adair County43.6+0.1
34Delaware County43.60
36Louisa County43.5+0.2
36Van Buren County43.5-0.1
38Harrison County43.4+0.2
38Keokuk County43.4+0.1
38Mitchell County43.4+0.1
41Palo Alto County43.3-0.7
42Ida County43.20
42Iowa County43.2+0.3
44Lucas County43.1-0.4
44Monroe County43.1+0.3
44Winnebago County43.1+0.3
47Allamakee County43-0.3
47Des Moines County43+0.1
49Emmet County42.9-0.4
49Floyd County42.9-0.2
49Mills County42.9-0.2
52Clay County42.80
53Clinton County42.7+0.2
54Franklin County42.60
55Benton County42.5+0.3
55Boone County42.5+0.2
55Taylor County42.5-0.1
58Grundy County42.40
58Hamilton County42.4-0.2
60Carroll County42.20
60Henry County42.2+1.2
60Howard County42.2+0.6
60Tama County42.2+0.2
64Jasper County42.1+0.2
65Humboldt County41.9+0.3
65Madison County41.9+0.2
67Union County41.6+0.1
68Plymouth County41.3+0.1
69Marion County41.20
69Washington County41.20
71Poweshiek County41.1+0.3
72Muscatine County40.8+0.4
73Pottawattamie County40.7+0.2
74Clarke County40.5+0.1
74O'Brien County40.5-0.5
76Buchanan County40.3+0.1
77Wright County40.2-0.3
78Bremer County40+0.2
78Wayne County400
80Webster County39.90
81Mahaska County39.70
81Scott County39.7+0.2
83Dubuque County39.6+0.3
84Wapello County39.1-0.2
85Linn County39+0.2
86Warren County38.80
87Marshall County38.6-0.1
88Crawford County38.1+0.1
89Lyon County37.4-0.2
90Decatur County37.2-0.7
91Black Hawk County36.6-0.1
92Polk County36.5+0.1
93Dallas County36.3+0.3
94Buena Vista County36.10
94Davis County36.1-0.1
96Woodbury County36+0.1
97Sioux County33.6+0.1
98Johnson County31.9+0.3
99Story County26.4-0.2

Other periods

About this ranking

Age that divides the resident population of a US county into two halves of equal size on 1 July, from Census Bureau population estimates calculated by single year of age.

Counties only: the county file has no state or national medians, and medians cannot be added up. A single-year estimate, unlike median_age, which for US places is a five-year American Community Survey estimate.

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: median age (MEDIAN_AGE_TOT) on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage. 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: median age (MEDIAN_AGE_TOT) on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage (Counties in Iowa by median age on 1 July (US county estimates), 2023) [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: median age (MEDIAN_AGE_TOT) on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage, Counties in Iowa by median age on 1 July (US county estimates), 2023. U.S. Census Bureau, 25 June 2026, https://www.census.gov/programs-surveys/popest/data/data-sets.html. Invokely, https://invokely.ai/rankings/median-age-july-1-us-counties/iowa-counties?period=2023. Accessed 12 Oct. 2026.

Chicago (author-date)

U.S. Census Bureau. 2026. Population Estimates Program, county population by age and sex: median age (MEDIAN_AGE_TOT) on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage. Counties in Iowa by median age on 1 July (US county estimates), 2023. Dataset. Accessed October 12, 2026. https://www.census.gov/programs-surveys/popest/data/data-sets.html. Also distributed by Invokely, https://invokely.ai/rankings/median-age-july-1-us-counties/iowa-counties?period=2023.

Harvard

U.S. Census Bureau (2026) Population Estimates Program, county population by age and sex: median age (MEDIAN_AGE_TOT) on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage, Counties in Iowa by median age on 1 July (US county estimates), 2023 [Dataset]. Available at: https://www.census.gov/programs-surveys/popest/data/data-sets.html, via Invokely: https://invokely.ai/rankings/median-age-july-1-us-counties/iowa-counties?period=2023 (Accessed: 12 October 2026).

BibTeX
@misc{census_counties_in_iowa_by_2023,
  author = {{U.S. Census Bureau}},
  title = {{Population Estimates Program, county population by age and sex: median age (MEDIAN\_AGE\_TOT) on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage: Counties in Iowa by median age on 1 July (US county estimates), 2023}},
  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/median-age-july-1-us-counties/iowa-counties?period=2023. Publisher attribution: U.S. Census Bureau. Population Estimates Program, county population by age and sex: median age (MEDIAN\_AGE\_TOT) on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage. 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: median age (MEDIAN_AGE_TOT) on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage: Counties in Iowa by median age on 1 July (US county estimates), 2023
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/median-age-july-1-us-counties/iowa-counties?period=2023
Y2  - 2026/10/12
N1  - Accessed via Invokely, https://invokely.ai/rankings/median-age-july-1-us-counties/iowa-counties?period=2023.
N1  - Publisher attribution: U.S. Census Bureau. Population Estimates Program, county population by age and sex: median age (MEDIAN_AGE_TOT) on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage. 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 median age on 1 July (US county estimates)?

Dickinson County, with 49.5 years in 2023, according to the U.S. Census Bureau.

Which county has the lowest median age on 1 July (US county estimates)?

Story County, with 26.4 years in 2023.

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: median age (MEDIAN_AGE_TOT) on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage. Retrieved 2026-10-12.

Median age on 1 July (US county estimates): other rankings

Counties in Iowa: more rankings