Counties in California by foreign-born share of the population

Santa Clara County had the highest foreign-born share of the population of 58 counties in 2022, at 40.4%. Sierra County had the lowest, at 2.6%. The median was 18.7% and the figure for California was 26.5%. Source: the U.S. Census Bureau.

Lowest2.6Sierra County
Median18.758 counties
California26.5History

All counties, 2022

CSVChart (SVG)

Santa Clara CountySanta Clara County: 40.4 %40.4San Mateo CountySan Mateo County: 35.2 %35.2San Francisco CountySan Francisco County: 33.9 %33.9Los Angeles CountyLos Angeles County: 33.3 %33.3Alameda CountyAlameda County: 33.3 %33.3Imperial CountyImperial County: 30.6 %30.6Orange CountyOrange County: 29.5 %29.5Monterey CountyMonterey County: 28.9 %28.9Colusa CountyColusa County: 28.6 %28.6Merced CountyMerced County: 26.3 %26.3Contra Costa CountyContra Costa County: 25.4 %25.4San Joaquin CountySan Joaquin County: 24 %24San Diego CountySan Diego County: 22.6 %22.6Napa CountyNapa County: 22.2 %22.2Santa Barbara CountySanta Barbara County: 22.2 %22.2Tulare CountyTulare County: 22.1 %22.1Yolo CountyYolo County: 22 %22Sutter CountySutter County: 21.7 %21.7Riverside CountyRiverside County: 21.7 %21.7Ventura CountyVentura County: 21.4 %21.4Sacramento CountySacramento County: 21.2 %21.2San Bernardino CountySan Bernardino County: 21.1 %21.1Madera CountyMadera County: 20.3 %20.3Stanislaus CountyStanislaus County: 20.2 %20.2Fresno CountyFresno County: 19.9 %19.9Kern CountyKern County: 19.7 %19.7Solano CountySolano County: 19.7 %19.7San Benito CountySan Benito County: 19.4 %19.4Mono CountyMono County: 18.8 %18.8Marin CountyMarin County: 18.6 %18.6Kings CountyKings County: 18.5 %18.5Santa Cruz CountySanta Cruz County: 17.4 %17.4Sonoma CountySonoma County: 16.3 %16.3Glenn CountyGlenn County: 15.1 %15.1Yuba CountyYuba County: 12.5 %12.5Placer CountyPlacer County: 12 %12Mendocino CountyMendocino County: 11.3 %11.3Tehama CountyTehama County: 9.8 %9.8Lake CountyLake County: 9.7 %9.7San Luis Obispo CountySan Luis Obispo County: 9.5 %9.5El Dorado CountyEl Dorado County: 9.3 %9.3Mariposa CountyMariposa County: 7.9 %7.9Del Norte CountyDel Norte County: 7.6 %7.6Butte CountyButte County: 7.6 %7.6Trinity CountyTrinity County: 7.4 %7.4Inyo CountyInyo County: 7.2 %7.2Nevada CountyNevada County: 6.4 %6.4Humboldt CountyHumboldt County: 6.2 %6.2Modoc CountyModoc County: 6.1 %6.1Siskiyou CountySiskiyou County: 6 %6Amador CountyAmador County: 5.8 %5.8Lassen CountyLassen County: 5.5 %5.5Calaveras CountyCalaveras County: 5.2 %5.2Shasta CountyShasta County: 5.2 %5.2Tuolumne CountyTuolumne County: 5 %5Plumas CountyPlumas County: 3.9 %3.9Alpine CountyAlpine County: 3.4 %3.4Sierra CountySierra County: 2.6 %2.6
%. Source: Invokely calculation with data from U.S. Census Bureau. Retrieved 2026-10-09.

Full ranking

RankCounties2022 (%)Change on 2021
1Santa Clara County40.4+0.4 pts
2San Mateo County35.20 pts
3San Francisco County33.9-0.3 pts
4Los Angeles County33.3-0.1 pts
5Alameda County33.3+0.3 pts
6Imperial County30.6+0.6 pts
7Orange County29.5+0.1 pts
8Monterey County28.9-0.1 pts
9Colusa County28.6+1.9 pts
10Merced County26.3+0.3 pts
11Contra Costa County25.4+0.4 pts
12San Joaquin County24+0.6 pts
13San Diego County22.6-0.2 pts
14Napa County22.2+0.7 pts
14Santa Barbara County22.2-0.2 pts
16Tulare County22.1+0.4 pts
17Yolo County22-0.4 pts
18Sutter County21.7-0.1 pts
19Riverside County21.7+0.1 pts
20Ventura County21.4+0.3 pts
21Sacramento County21.2+0.2 pts
22San Bernardino County21.1+0.5 pts
23Madera County20.3+0.4 pts
24Stanislaus County20.2+0.1 pts
25Fresno County19.9-0 pts
26Kern County19.7+0.1 pts
27Solano County19.7-0.1 pts
28San Benito County19.4-0.6 pts
29Mono County18.8+2 pts
30Marin County18.6+0.1 pts
31Kings County18.5-0.7 pts
32Santa Cruz County17.4-0.4 pts
33Sonoma County16.3-0 pts
34Glenn County15.1-1 pts
35Yuba County12.5-0.2 pts
36Placer County12+0.3 pts
37Mendocino County11.3-1.1 pts
38Tehama County9.8+1.3 pts
39Lake County9.7+0.7 pts
40San Luis Obispo County9.5-0.2 pts
41El Dorado County9.3+0.1 pts
42Mariposa County7.9+2.3 pts
43Del Norte County7.6-0.6 pts
44Butte County7.6-0.1 pts
45Trinity County7.4-0.4 pts
46Inyo County7.2+0.1 pts
47Nevada County6.4+0.3 pts
48Humboldt County6.2+0.1 pts
49Modoc County6.1-1.1 pts
50Siskiyou County6+0.2 pts
51Amador County5.8-0.5 pts
52Lassen County5.5+0.1 pts
53Calaveras County5.2+0.5 pts
54Shasta County5.2-0.4 pts
55Tuolumne County5-0.3 pts
56Plumas County3.9+0.2 pts
57Alpine County3.4-1.4 pts
58Sierra County2.6-0.7 pts

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/2022/table-based-SF/data/5YRData/acsdt5y2022-b05002.dat. Retrieved 2026-10-09.

Use this data in your AI agent

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Rank Counties in California by foreign-born share of the population using official data, and cite the source.
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Questions

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

Santa Clara County, with 40.4% in 2022, according to the U.S. Census Bureau.

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

Sierra County, with 2.6% in 2022.

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 California: more rankings