Counties in Iowa by foreign-born share of the population

Buena Vista County had the highest foreign-born share of the population of 99 counties in 2021, at 20.6%. Adams County had the lowest, at 0.3%. The median was 1.9% and the figure for Iowa was 5.5%. Source: the U.S. Census Bureau.

Lowest0.3Adams County
Median1.999 counties
Iowa5.5History

Top 40 counties, 2021

CSVChart (SVG)

Buena Vista CountyBuena Vista County: 20.6 %20.6Crawford CountyCrawford County: 16.9 %16.9Marshall CountyMarshall County: 13.2 %13.2Jefferson CountyJefferson County: 12 %12Johnson CountyJohnson County: 10.8 %10.8Louisa CountyLouisa County: 9.6 %9.6Woodbury CountyWoodbury County: 9.5 %9.5Polk CountyPolk County: 9.4 %9.4Story CountyStory County: 9.2 %9.2Dallas CountyDallas County: 9 %9Wapello CountyWapello County: 7.4 %7.4Muscatine CountyMuscatine County: 6.8 %6.8Clarke CountyClarke County: 6.8 %6.8Black Hawk CountyBlack Hawk County: 6.5 %6.5Sioux CountySioux County: 5.8 %5.8Emmet CountyEmmet County: 5.6 %5.6Tama CountyTama County: 5.4 %5.4Allamakee CountyAllamakee County: 5.3 %5.3Osceola CountyOsceola County: 5.2 %5.2Franklin CountyFranklin County: 5 %5Linn CountyLinn County: 5 %5Taylor CountyTaylor County: 4.7 %4.7Scott CountyScott County: 4.2 %4.2Wright CountyWright County: 4.1 %4.1Henry CountyHenry County: 4 %4Pottawattamie CountyPottawattamie County: 4 %4Floyd CountyFloyd County: 3.8 %3.8Hamilton CountyHamilton County: 3.6 %3.6Plymouth CountyPlymouth County: 3.6 %3.6Washington CountyWashington County: 3.6 %3.6Hardin CountyHardin County: 3.2 %3.2Winnebago CountyWinnebago County: 3.1 %3.1Humboldt CountyHumboldt County: 2.9 %2.9Lucas CountyLucas County: 2.8 %2.8Dubuque CountyDubuque County: 2.8 %2.8Pocahontas CountyPocahontas County: 2.7 %2.7Poweshiek CountyPoweshiek County: 2.7 %2.7Webster CountyWebster County: 2.6 %2.6O'Brien CountyO'Brien County: 2.5 %2.5Cherokee CountyCherokee County: 2.4 %2.4
%. Source: Invokely calculation with data from U.S. Census Bureau. Retrieved 2026-10-09.

Full ranking

RankCounties2021 (%)
1Buena Vista County20.6
2Crawford County16.9
3Marshall County13.2
4Jefferson County12
5Johnson County10.8
6Louisa County9.6
7Woodbury County9.5
8Polk County9.4
9Story County9.2
10Dallas County9
11Wapello County7.4
12Muscatine County6.8
13Clarke County6.8
14Black Hawk County6.5
15Sioux County5.8
16Emmet County5.6
17Tama County5.4
18Allamakee County5.3
19Osceola County5.2
20Franklin County5
21Linn County5
22Taylor County4.7
23Scott County4.2
24Wright County4.1
25Henry County4
25Pottawattamie County4
27Floyd County3.8
28Hamilton County3.6
28Plymouth County3.6
30Washington County3.6
31Hardin County3.2
32Winnebago County3.1
33Humboldt County2.9
34Lucas County2.8
35Dubuque County2.8
36Pocahontas County2.7
37Poweshiek County2.7
38Webster County2.6
39O'Brien County2.5
40Cherokee County2.4
41Palo Alto County2.4
42Jasper County2.3
43Winneshiek County2.2
44Marion County2.2
45Decatur County2.1
46Dickinson County2
47Des Moines County2
47Shelby County2
49Bremer County2
50Union County1.9
51Cerro Gordo County1.9
52Lyon County1.9
53Carroll County1.9
54Mahaska County1.9
55Kossuth County1.8
56Clayton County1.8
57Boone County1.7
57Sac County1.7
59Guthrie County1.7
60Warren County1.6
61Cedar County1.6
61Lee County1.6
61Mitchell County1.6
64Cass County1.6
65Grundy County1.6
66Davis County1.6
66Hancock County1.6
68Butler County1.6
69Greene County1.5
70Fayette County1.5
70Page County1.5
72Clay County1.4
73Buchanan County1.4
74Calhoun County1.4
74Van Buren County1.4
76Ida County1.3
77Monroe County1.3
78Chickasaw County1.3
78Clinton County1.3
80Mills County1.3
81Adair County1.3
81Madison County1.3
83Howard County1.1
84Jackson County1.1
85Wayne County1
86Iowa County1
87Fremont County1
87Keokuk County1
89Audubon County0.9
90Appanoose County0.8
91Jones County0.8
92Benton County0.7
93Worth County0.7
94Montgomery County0.7
95Ringgold County0.6
96Harrison County0.6
97Delaware County0.5
98Monona County0.4
99Adams County0.3

Other periods

About this ranking

People who were not US citizens at birth, as a percentage of the total population. Includes naturalized citizens, lawful permanent residents, temporary migrants and unauthorized immigrants. United States: American Community Survey five-year estimate, where the period shown is the last year of the five-year span.

Based on place of birth, not nationality: a naturalized citizen counts as foreign born, and people born in Puerto Rico, the US island areas or abroad to American parents count as native. Not comparable with foreign_population_share, which counts foreign nationals in Spain and the EU. Calculated from counts in ACS table B05002, which are stored as inputs.

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 B05002: foreign-born population as a percentage of the total population, calculated with stored inputs. https://www2.census.gov/programs-surveys/acs/summary_file/2021/table-based-SF/data/5YRData/acsdt5y2021-b05002.dat. Retrieved 2026-10-09.

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Questions

Which county has the highest foreign-born share of the population?

Buena Vista County, with 20.6% in 2021, according to the U.S. Census Bureau.

Which county has the lowest foreign-born share of the population?

Adams County, with 0.3% 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 B05002: foreign-born population as a percentage of the total population, calculated with stored inputs. Retrieved 2026-10-09.

Foreign-born population share: other rankings

Counties in Iowa: more rankings