Counties in California by foreign-born share of the population, 2024

Santa Clara County had the highest foreign-born share of the population of 58 counties in 2024, at 41.5%. Sierra County had the lowest, at 3.8%. The median was 19.4% and the figure for California was 27%. Source: the U.S. Census Bureau.

Lowest3.8Sierra County
Median19.458 counties
California27History

All counties, 2024

CSVChart (SVG)

Santa Clara CountySanta Clara County: 41.5 %41.5San Mateo CountySan Mateo County: 35.7 %35.7Alameda CountyAlameda County: 34.7 %34.7San Francisco CountySan Francisco County: 34.1 %34.1Los Angeles CountyLos Angeles County: 33.4 %33.4Imperial CountyImperial County: 31.6 %31.6Orange CountyOrange County: 30.4 %30.4Monterey CountyMonterey County: 29.6 %29.6Colusa CountyColusa County: 27.5 %27.5Contra Costa CountyContra Costa County: 26.6 %26.6Merced CountyMerced County: 25.6 %25.6San Joaquin CountySan Joaquin County: 25.2 %25.2San Diego CountySan Diego County: 22.8 %22.8Sutter CountySutter County: 22.7 %22.7Sacramento CountySacramento County: 22.3 %22.3Ventura CountyVentura County: 22.2 %22.2Tulare CountyTulare County: 22.2 %22.2Napa CountyNapa County: 22.2 %22.2Santa Barbara CountySanta Barbara County: 22.2 %22.2Riverside CountyRiverside County: 21.9 %21.9San Bernardino CountySan Bernardino County: 21.6 %21.6Stanislaus CountyStanislaus County: 21 %21Yolo CountyYolo County: 21 %21Solano CountySolano County: 20.8 %20.8Kern CountyKern County: 20.2 %20.2Madera CountyMadera County: 20.1 %20.1San Benito CountySan Benito County: 20 %20Fresno CountyFresno County: 20 %20Marin CountyMarin County: 19.6 %19.6Kings CountyKings County: 19.2 %19.2Glenn CountyGlenn County: 18.6 %18.6Santa Cruz CountySanta Cruz County: 18 %18Sonoma CountySonoma County: 16.8 %16.8Mono CountyMono County: 14.1 %14.1Placer CountyPlacer County: 12.7 %12.7Mendocino CountyMendocino County: 12.2 %12.2Yuba CountyYuba County: 11.5 %11.5Tehama CountyTehama County: 11.1 %11.1Lake CountyLake County: 9.9 %9.9San Luis Obispo CountySan Luis Obispo County: 9.9 %9.9El Dorado CountyEl Dorado County: 9.2 %9.2Modoc CountyModoc County: 8.8 %8.8Butte CountyButte County: 8.6 %8.6Mariposa CountyMariposa County: 8.3 %8.3Inyo CountyInyo County: 7.9 %7.9Lassen CountyLassen County: 7 %7Del Norte CountyDel Norte County: 6.8 %6.8Nevada CountyNevada County: 6.4 %6.4Humboldt CountyHumboldt County: 6.2 %6.2Calaveras CountyCalaveras County: 6.1 %6.1Siskiyou CountySiskiyou County: 5.8 %5.8Amador CountyAmador County: 5.8 %5.8Alpine CountyAlpine County: 5.4 %5.4Shasta CountyShasta County: 5 %5Plumas CountyPlumas County: 4.8 %4.8Trinity CountyTrinity County: 4.8 %4.8Tuolumne CountyTuolumne County: 4.6 %4.6Sierra CountySierra County: 3.8 %3.8
%. Source: Invokely calculation with data from U.S. Census Bureau. Retrieved 2026-10-09.

Full ranking

RankCounties2024 (%)Change on 2023
1Santa Clara County41.5+0.5 pts
2San Mateo County35.7+0.1 pts
3Alameda County34.7+0.6 pts
4San Francisco County34.1-0.2 pts
5Los Angeles County33.4+0.1 pts
6Imperial County31.6+0.9 pts
7Orange County30.4+0.5 pts
8Monterey County29.6+0.8 pts
9Colusa County27.5-0 pts
10Contra Costa County26.6+0.4 pts
11Merced County25.6-0.5 pts
12San Joaquin County25.2+0.7 pts
13San Diego County22.8+0.3 pts
14Sutter County22.7+0.4 pts
15Sacramento County22.3+0.8 pts
16Ventura County22.2+0.3 pts
17Tulare County22.2+0.4 pts
18Napa County22.2+0.1 pts
19Santa Barbara County22.2+0.1 pts
20Riverside County21.9+0.3 pts
21San Bernardino County21.6+0.2 pts
22Stanislaus County21+0.5 pts
23Yolo County21-0.7 pts
24Solano County20.8+0.3 pts
25Kern County20.2+0.5 pts
26Madera County20.1-0.1 pts
27San Benito County20+0.8 pts
28Fresno County20+0.3 pts
29Marin County19.60 pts
30Kings County19.2-0.3 pts
31Glenn County18.6+2.8 pts
32Santa Cruz County18+0.3 pts
33Sonoma County16.8+0.2 pts
34Mono County14.1-2.2 pts
35Placer County12.7+0.4 pts
36Mendocino County12.2+0.6 pts
37Yuba County11.5+0.5 pts
38Tehama County11.1+0.3 pts
39Lake County9.9+0.5 pts
40San Luis Obispo County9.9+0.2 pts
41El Dorado County9.2+0.1 pts
42Modoc County8.8+2.2 pts
43Butte County8.6+0.5 pts
44Mariposa County8.3+0.3 pts
45Inyo County7.9-0.3 pts
46Lassen County7+1 pts
47Del Norte County6.8-0.8 pts
48Nevada County6.4-0.2 pts
49Humboldt County6.2-0.3 pts
50Calaveras County6.1+0.3 pts
51Siskiyou County5.8-0.1 pts
52Amador County5.8-0.2 pts
53Alpine County5.4+0.6 pts
54Shasta County5+0.2 pts
55Plumas County4.8+1.3 pts
56Trinity County4.8-1.5 pts
57Tuolumne County4.6-0.5 pts
58Sierra County3.8+1.4 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/2024/table-based-SF/data/5YRData/acsdt5y2024-b05002.dat. Retrieved 2026-10-09.

Use this data in your AI agent

Invokely serves this figure to AI assistants through MCP and to code through a REST API, with the source and citation attached. Ask your assistant:

Rank Counties in California by foreign-born share of the population using official data, and cite the source.
rank_places {"indicator":"foreign_born_share","level":"province","within":"California","limit":10}
GET https://invokely.ai/api/v1/rank?indicator=foreign_born_share&level=province&within=California&limit=10

Connect Claude, ChatGPT or Cursor in one step. The trial answers 25 calls a day without an account.

Questions

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

Santa Clara County, with 41.5% in 2024, according to the U.S. Census Bureau.

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

Sierra County, with 3.8% in 2024.

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