Counties in Iowa by average household size

Davis County had the highest average household size of 99 counties in 2021, at 2.9 persons per household. Dickinson County had the lowest, at 2.1 persons per household. The median was 2.4 persons per household and the figure for Iowa was 2.4 persons per household. Source: the U.S. Census Bureau.

Keep it in a collection in your library.
Highest2.9Davis County
Median2.499 counties
Iowa2.4History

Map of counties, 2021

Adair County: 2.3 persons per householdAdams County: 2.3 persons per householdAllamakee County: 2.4 persons per householdAppanoose County: 2.5 persons per householdAudubon County: 2.2 persons per householdBenton County: 2.5 persons per householdBlack Hawk County: 2.4 persons per householdBoone County: 2.5 persons per householdBremer County: 2.4 persons per householdBuchanan County: 2.6 persons per householdBuena Vista County: 2.6 persons per householdButler County: 2.4 persons per householdCalhoun County: 2.4 persons per householdCarroll County: 2.3 persons per householdCass County: 2.2 persons per householdCedar County: 2.5 persons per householdCerro Gordo County: 2.2 persons per householdCherokee County: 2.2 persons per householdChickasaw County: 2.4 persons per householdClarke County: 2.6 persons per householdClay County: 2.3 persons per householdClayton County: 2.3 persons per householdClinton County: 2.4 persons per householdCrawford County: 2.6 persons per householdDallas County: 2.5 persons per householdDavis County: 2.9 persons per householdDecatur County: 2.3 persons per householdDelaware County: 2.5 persons per householdDes Moines County: 2.3 persons per householdDickinson County: 2.1 persons per householdDubuque County: 2.4 persons per householdEmmet County: 2.3 persons per householdFayette County: 2.3 persons per householdFloyd County: 2.3 persons per householdFranklin County: 2.4 persons per householdFremont County: 2.4 persons per householdGreene County: 2.3 persons per householdGrundy County: 2.4 persons per householdGuthrie County: 2.3 persons per householdHamilton County: 2.5 persons per householdHancock County: 2.3 persons per householdHardin County: 2.3 persons per householdHarrison County: 2.4 persons per householdHenry County: 2.5 persons per householdHoward County: 2.5 persons per householdHumboldt County: 2.3 persons per householdIda County: 2.3 persons per householdIowa County: 2.4 persons per householdJackson County: 2.4 persons per householdJasper County: 2.5 persons per householdJefferson County: 2.2 persons per householdJohnson County: 2.4 persons per householdJones County: 2.4 persons per householdKeokuk County: 2.4 persons per householdKossuth County: 2.3 persons per householdLee County: 2.3 persons per householdLinn County: 2.4 persons per householdLouisa County: 2.7 persons per householdLucas County: 2.4 persons per householdLyon County: 2.7 persons per householdMadison County: 2.6 persons per householdMahaska County: 2.4 persons per householdMarion County: 2.4 persons per householdMarshall County: 2.5 persons per householdMills County: 2.7 persons per householdMitchell County: 2.4 persons per householdMonona County: 2.3 persons per householdMonroe County: 2.5 persons per householdMontgomery County: 2.3 persons per householdMuscatine County: 2.5 persons per householdO'Brien County: 2.4 persons per householdOsceola County: 2.3 persons per householdPage County: 2.3 persons per householdPalo Alto County: 2.4 persons per householdPlymouth County: 2.5 persons per householdPocahontas County: 2.2 persons per householdPolk County: 2.5 persons per householdPottawattamie County: 2.5 persons per householdPoweshiek County: 2.2 persons per householdRinggold County: 2.5 persons per householdSac County: 2.3 persons per householdScott County: 2.4 persons per householdShelby County: 2.4 persons per householdSioux County: 2.7 persons per householdStory County: 2.3 persons per householdTama County: 2.5 persons per householdTaylor County: 2.4 persons per householdUnion County: 2.4 persons per householdVan Buren County: 2.5 persons per householdWapello County: 2.5 persons per householdWarren County: 2.6 persons per householdWashington County: 2.5 persons per householdWayne County: 2.5 persons per householdWebster County: 2.2 persons per householdWinnebago County: 2.3 persons per householdWinneshiek County: 2.2 persons per householdWoodbury County: 2.6 persons per householdWorth County: 2.3 persons per householdWright County: 2.4 persons per household
  • Under 2.3
  • 2.3 to 2.4
  • 2.4 to 2.5
  • 2.5 and over
persons per household, 2021. Source: U.S. Census Bureau, American Community Survey 5-year estimates, table B25010: average household size of occupied housing units. Boundaries: U.S. Census Bureau cartographic boundary files.

Top 40 counties, 2021

Davis County: 2.9 persons per householdDavis County2.9Sioux County: 2.7 persons per householdSioux County2.7Lyon County: 2.7 persons per householdLyon County2.7Mills County: 2.7 persons per householdMills County2.7Louisa County: 2.7 persons per householdLouisa County2.7Buena Vista County: 2.6 persons per householdBuena Vista County2.6Buchanan County: 2.6 persons per householdBuchanan County2.6Crawford County: 2.6 persons per householdCrawford County2.6Warren County: 2.6 persons per householdWarren County2.6Woodbury County: 2.6 persons per householdWoodbury County2.6Clarke County: 2.6 persons per householdClarke County2.6Madison County: 2.6 persons per householdMadison County2.6Marshall County: 2.5 persons per householdMarshall County2.5Dallas County: 2.5 persons per householdDallas County2.5Muscatine County: 2.5 persons per householdMuscatine County2.5Wayne County: 2.5 persons per householdWayne County2.5Benton County: 2.5 persons per householdBenton County2.5Tama County: 2.5 persons per householdTama County2.5Henry County: 2.5 persons per householdHenry County2.5Washington County: 2.5 persons per householdWashington County2.5Howard County: 2.5 persons per householdHoward County2.5Jasper County: 2.5 persons per householdJasper County2.5Delaware County: 2.5 persons per householdDelaware County2.5Hamilton County: 2.5 persons per householdHamilton County2.5Monroe County: 2.5 persons per householdMonroe County2.5Van Buren County: 2.5 persons per householdVan Buren County2.5Appanoose County: 2.5 persons per householdAppanoose County2.5Plymouth County: 2.5 persons per householdPlymouth County2.5Pottawattamie County: 2.5 persons per householdPottawattamie County2.5Cedar County: 2.5 persons per householdCedar County2.5Polk County: 2.5 persons per householdPolk County2.5Boone County: 2.5 persons per householdBoone County2.5Ringgold County: 2.5 persons per householdRinggold County2.5Wapello County: 2.5 persons per householdWapello County2.5Mahaska County: 2.4 persons per householdMahaska County2.4Scott County: 2.4 persons per householdScott County2.4Butler County: 2.4 persons per householdButler County2.4Grundy County: 2.4 persons per householdGrundy County2.4Jones County: 2.4 persons per householdJones County2.4O'Brien County: 2.4 persons per householdO'Brien County2.4Davis County: 2.9 persons per householdDavis County2.9Sioux County: 2.7 persons per householdSioux County2.7Lyon County: 2.7 persons per householdLyon County2.7Mills County: 2.7 persons per householdMills County2.7Louisa County: 2.7 persons per householdLouisa County2.7Buena Vista County: 2.6 persons per householdBuena Vista County2.6Buchanan County: 2.6 persons per householdBuchanan County2.6Crawford County: 2.6 persons per householdCrawford County2.6Warren County: 2.6 persons per householdWarren County2.6Woodbury County: 2.6 persons per householdWoodbury County2.6Clarke County: 2.6 persons per householdClarke County2.6Madison County: 2.6 persons per householdMadison County2.6Marshall County: 2.5 persons per householdMarshall County2.5Dallas County: 2.5 persons per householdDallas County2.5Muscatine County: 2.5 persons per householdMuscatine County2.5Wayne County: 2.5 persons per householdWayne County2.5Benton County: 2.5 persons per householdBenton County2.5Tama County: 2.5 persons per householdTama County2.5Henry County: 2.5 persons per householdHenry County2.5Washington County: 2.5 persons per householdWashington County2.5Howard County: 2.5 persons per householdHoward County2.5Jasper County: 2.5 persons per householdJasper County2.5Delaware County: 2.5 persons per householdDelaware County2.5Hamilton County: 2.5 persons per householdHamilton County2.5Monroe County: 2.5 persons per householdMonroe County2.5Van Buren County: 2.5 persons per householdVan Buren County2.5Appanoose County: 2.5 persons per householdAppanoose County2.5Plymouth County: 2.5 persons per householdPlymouth County2.5Pottawattamie County: 2.5 persons per householdPottawattamie County2.5Cedar County: 2.5 persons per householdCedar County2.5Polk County: 2.5 persons per householdPolk County2.5Boone County: 2.5 persons per householdBoone County2.5Ringgold County: 2.5 persons per householdRinggold County2.5Wapello County: 2.5 persons per householdWapello County2.5Mahaska County: 2.4 persons per householdMahaska County2.4Scott County: 2.4 persons per householdScott County2.4Butler County: 2.4 persons per householdButler County2.4Grundy County: 2.4 persons per householdGrundy County2.4Jones County: 2.4 persons per householdJones County2.4O'Brien County: 2.4 persons per householdO'Brien County2.4
persons per household. Source: U.S. Census Bureau, American Community Survey 5-year estimates, table B25010: average household size of occupied housing units. Retrieved 2026-10-12.

Full ranking

RankCounties2021
persons per household
1Davis County2.9
2Sioux County2.7
3Lyon County2.7
4Mills County2.7
5Louisa County2.7
6Buena Vista County2.6
7Buchanan County2.6
8Crawford County2.6
9Warren County2.6
9Woodbury County2.6
11Clarke County2.6
12Madison County2.6
13Marshall County2.5
14Dallas County2.5
14Muscatine County2.5
14Wayne County2.5
17Benton County2.5
17Tama County2.5
19Henry County2.5
19Washington County2.5
21Howard County2.5
21Jasper County2.5
23Delaware County2.5
23Hamilton County2.5
23Monroe County2.5
23Van Buren County2.5
27Appanoose County2.5
27Plymouth County2.5
27Pottawattamie County2.5
30Cedar County2.5
31Polk County2.5
32Boone County2.5
32Ringgold County2.5
32Wapello County2.5
35Mahaska County2.4
35Scott County2.4
37Butler County2.4
37Grundy County2.4
37Jones County2.4
37O'Brien County2.4
41Bremer County2.4
41Harrison County2.4
43Franklin County2.4
43Fremont County2.4
43Iowa County2.4
43Union County2.4
47Clinton County2.4
47Dubuque County2.4
47Jackson County2.4
47Keokuk County2.4
47Marion County2.4
52Johnson County2.4
52Linn County2.4
52Taylor County2.4
52Wright County2.4
56Allamakee County2.4
57Black Hawk County2.4
57Chickasaw County2.4
57Lucas County2.4
60Palo Alto County2.4
61Calhoun County2.4
61Mitchell County2.4
61Shelby County2.4
64Adams County2.3
64Fayette County2.3
64Guthrie County2.3
67Carroll County2.3
67Ida County2.3
67Worth County2.3
70Montgomery County2.3
71Clayton County2.3
71Decatur County2.3
71Hancock County2.3
71Hardin County2.3
71Lee County2.3
76Adair County2.3
76Floyd County2.3
76Greene County2.3
76Page County2.3
76Sac County2.3
81Osceola County2.3
81Story County2.3
83Humboldt County2.3
83Kossuth County2.3
85Clay County2.3
85Monona County2.3
85Winnebago County2.3
88Des Moines County2.3
88Emmet County2.3
90Cass County2.2
90Jefferson County2.2
90Pocahontas County2.2
93Audubon County2.2
94Winneshiek County2.2
95Webster County2.2
96Cherokee County2.2
96Poweshiek County2.2
98Cerro Gordo County2.2
99Dickinson County2.1

Other periods

About this ranking

Average number of persons per private household. EU countries: EU-SILC. United States: American Community Survey five-year estimate of people in households divided by occupied housing units, where the period shown is the last year of the five-year span.

Covers private households only; people living in institutions or other group quarters are excluded. EU-SILC figures refer to the survey year. The EU and US surveys differ, so their figures are not strictly comparable.

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 B25010: average household size of occupied housing units. https://www2.census.gov/programs-surveys/acs/summary_file/2021/table-based-SF/data/5YRData/acsdt5y2021-b25010.dat. 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). American Community Survey 5-year estimates, table B25010: average household size of occupied housing units (Counties in Iowa by average household size, 2021) [Data set]. Retrieved October 12, 2026, from https://www2.census.gov/programs-surveys/acs/summary_file/2021/table-based-SF/data/5YRData/acsdt5y2021-b25010.dat

MLA 9

American Community Survey 5-year estimates, table B25010: average household size of occupied housing units, Counties in Iowa by average household size, 2021. U.S. Census Bureau, 29 Jan. 2026, https://www2.census.gov/programs-surveys/acs/summary_file/2021/table-based-SF/data/5YRData/acsdt5y2021-b25010.dat. Invokely, https://invokely.ai/rankings/average-household-size/iowa-counties?period=2021. Accessed 12 Oct. 2026.

Chicago (author-date)

U.S. Census Bureau. 2026. American Community Survey 5-year estimates, table B25010: average household size of occupied housing units. Counties in Iowa by average household size, 2021. Dataset. Accessed October 12, 2026. https://www2.census.gov/programs-surveys/acs/summary_file/2021/table-based-SF/data/5YRData/acsdt5y2021-b25010.dat. Also distributed by Invokely, https://invokely.ai/rankings/average-household-size/iowa-counties?period=2021.

Harvard

U.S. Census Bureau (2026) American Community Survey 5-year estimates, table B25010: average household size of occupied housing units, Counties in Iowa by average household size, 2021 [Dataset]. Available at: https://www2.census.gov/programs-surveys/acs/summary_file/2021/table-based-SF/data/5YRData/acsdt5y2021-b25010.dat, via Invokely: https://invokely.ai/rankings/average-household-size/iowa-counties?period=2021 (Accessed: 12 October 2026).

BibTeX
@misc{census_counties_in_iowa_by_2021,
  author = {{U.S. Census Bureau}},
  title = {{American Community Survey 5-year estimates, table B25010: average household size of occupied housing units: Counties in Iowa by average household size, 2021}},
  year = {2026},
  howpublished = {Data set},
  url = {https://www2.census.gov/programs-surveys/acs/summary_file/2021/table-based-SF/data/5YRData/acsdt5y2021-b25010.dat},
  urldate = {2026-10-12},
  note = {Accessed via Invokely, https://invokely.ai/rankings/average-household-size/iowa-counties?period=2021. Publisher attribution: U.S. Census Bureau. American Community Survey 5-year estimates, table B25010: average household size of occupied housing units. https://www2.census.gov/programs-surveys/acs/summary\_file/2021/table-based-SF/data/5YRData/acsdt5y2021-b25010.dat. Retrieved 2026-10-12.},
}
RIS
TY  - DATA
AU  - U.S. Census Bureau
TI  - American Community Survey 5-year estimates, table B25010: average household size of occupied housing units: Counties in Iowa by average household size, 2021
PY  - 2026
DA  - 2026/01/29
PB  - U.S. Census Bureau
DB  - Invokely
UR  - https://www2.census.gov/programs-surveys/acs/summary_file/2021/table-based-SF/data/5YRData/acsdt5y2021-b25010.dat
L2  - https://invokely.ai/rankings/average-household-size/iowa-counties?period=2021
Y2  - 2026/10/12
N1  - Accessed via Invokely, https://invokely.ai/rankings/average-household-size/iowa-counties?period=2021.
N1  - Publisher attribution: U.S. Census Bureau. American Community Survey 5-year estimates, table B25010: average household size of occupied housing units. https://www2.census.gov/programs-surveys/acs/summary_file/2021/table-based-SF/data/5YRData/acsdt5y2021-b25010.dat. Retrieved 2026-10-12.
ER  - 
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Questions

Which county has the highest average household size?

Davis County, with 2.9 persons per household in 2021, according to the U.S. Census Bureau.

Which county has the lowest average household size?

Dickinson County, with 2.1 persons per household 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 B25010: average household size of occupied housing units. Retrieved 2026-10-12.

Average household size: other rankings

Counties in Iowa: more rankings