Counties in California by uninsured rate, ages 35 to 64 (US, ACS)

Trinity County had the highest uninsured rate, ages 35 to 64 (US, ACS) of 58 counties in 2023, at 16.9%. Placer County had the lowest, at 3.7%. The median was 8.4% and the figure for California was 9.1%. Source: the U.S. Census Bureau.

Keep it in a collection in your library.
Highest16.9Trinity County
Lowest3.7Placer County
Median8.458 counties
California9.1History

Map of counties, 2023

Alameda County: 4.7 %Alpine County: 6.1 %Amador County: 8.3 %Butte County: 7.7 %Calaveras County: 8.4 %Colusa County: 12.7 %Contra Costa County: 5.7 %Del Norte County: 7.7 %El Dorado County: 4.9 %Fresno County: 9.5 %Glenn County: 9.5 %Humboldt County: 7.6 %Imperial County: 11.2 %Inyo County: 8.8 %Kern County: 11.3 %Kings County: 9.7 %Lake County: 8 %Lassen County: 7.6 %Los Angeles County: 11.5 %Madera County: 10.8 %Marin County: 4.9 %Mariposa County: 10.9 %Mendocino County: 11.9 %Merced County: 12.3 %Modoc County: 11.2 %Mono County: 14.7 %Monterey County: 13.9 %Napa County: 7.3 %Nevada County: 7.7 %Orange County: 9 %Placer County: 3.7 %Plumas County: 9.6 %Riverside County: 10.9 %Sacramento County: 6.3 %San Benito County: 9 %San Bernardino County: 11.4 %San Diego County: 8.6 %San Francisco County: 4.2 %San Joaquin County: 8.3 %San Luis Obispo County: 8.1 %San Mateo County: 4.5 %Santa Barbara County: 14.2 %Santa Clara County: 4.9 %Santa Cruz County: 7.2 %Shasta County: 7.7 %Sierra County: 7 %Siskiyou County: 8.9 %Solano County: 5.7 %Sonoma County: 7.7 %Stanislaus County: 8.5 %Sutter County: 8.3 %Tehama County: 8.6 %Trinity County: 16.9 %Tulare County: 12.2 %Tuolumne County: 8 %Ventura County: 11 %Yolo County: 5.9 %Yuba County: 8.1 %
  • Under 6
  • 6 to 7.7
  • 7.7 to 8.4
  • 8.4 to 9.5
  • 9.5 to 11
  • 11 and over
%, 2023. Source: Invokely calculation with data from U.S. Census Bureau. Boundaries: U.S. Census Bureau cartographic boundary files.

All counties, 2023

Trinity County: 16.9 %Trinity County16.9Mono County: 14.7 %Mono County14.7Santa Barbara County: 14.2 %Santa Barbara County14.2Monterey County: 13.9 %Monterey County13.9Colusa County: 12.7 %Colusa County12.7Merced County: 12.3 %Merced County12.3Tulare County: 12.2 %Tulare County12.2Mendocino County: 11.9 %Mendocino County11.9Los Angeles County: 11.5 %Los Angeles County11.5San Bernardino County: 11.4 %San Bernardino County11.4Kern County: 11.3 %Kern County11.3Imperial County: 11.2 %Imperial County11.2Modoc County: 11.2 %Modoc County11.2Ventura County: 11 %Ventura County11Riverside County: 10.9 %Riverside County10.9Mariposa County: 10.9 %Mariposa County10.9Madera County: 10.8 %Madera County10.8Kings County: 9.7 %Kings County9.7Plumas County: 9.6 %Plumas County9.6Glenn County: 9.5 %Glenn County9.5Fresno County: 9.5 %Fresno County9.5San Benito County: 9 %San Benito County9Orange County: 9 %Orange County9Siskiyou County: 8.9 %Siskiyou County8.9Inyo County: 8.8 %Inyo County8.8San Diego County: 8.6 %San Diego County8.6Tehama County: 8.6 %Tehama County8.6Stanislaus County: 8.5 %Stanislaus County8.5Calaveras County: 8.4 %Calaveras County8.4San Joaquin County: 8.3 %San Joaquin County8.3Amador County: 8.3 %Amador County8.3Sutter County: 8.3 %Sutter County8.3Yuba County: 8.1 %Yuba County8.1San Luis Obispo County: 8.1 %San Luis Obispo County8.1Lake County: 8 %Lake County8Tuolumne County: 8 %Tuolumne County8Butte County: 7.7 %Butte County7.7Nevada County: 7.7 %Nevada County7.7Shasta County: 7.7 %Shasta County7.7Del Norte County: 7.7 %Del Norte County7.7Sonoma County: 7.7 %Sonoma County7.7Lassen County: 7.6 %Lassen County7.6Humboldt County: 7.6 %Humboldt County7.6Napa County: 7.3 %Napa County7.3Santa Cruz County: 7.2 %Santa Cruz County7.2Sierra County: 7 %Sierra County7Sacramento County: 6.3 %Sacramento County6.3Alpine County: 6.1 %Alpine County6.1Yolo County: 5.9 %Yolo County5.9Solano County: 5.7 %Solano County5.7Contra Costa County: 5.7 %Contra Costa County5.7El Dorado County: 4.9 %El Dorado County4.9Santa Clara County: 4.9 %Santa Clara County4.9Marin County: 4.9 %Marin County4.9Alameda County: 4.7 %Alameda County4.7San Mateo County: 4.5 %San Mateo County4.5San Francisco County: 4.2 %San Francisco County4.2Placer County: 3.7 %Placer County3.7Trinity County: 16.9 %Trinity County16.9Mono County: 14.7 %Mono County14.7Santa Barbara County: 14.2 %Santa Barbara County14.2Monterey County: 13.9 %Monterey County13.9Colusa County: 12.7 %Colusa County12.7Merced County: 12.3 %Merced County12.3Tulare County: 12.2 %Tulare County12.2Mendocino County: 11.9 %Mendocino County11.9Los Angeles County: 11.5 %Los Angeles County11.5San Bernardino County: 11.4 %San Bernardino County11.4Kern County: 11.3 %Kern County11.3Imperial County: 11.2 %Imperial County11.2Modoc County: 11.2 %Modoc County11.2Ventura County: 11 %Ventura County11Riverside County: 10.9 %Riverside County10.9Mariposa County: 10.9 %Mariposa County10.9Madera County: 10.8 %Madera County10.8Kings County: 9.7 %Kings County9.7Plumas County: 9.6 %Plumas County9.6Glenn County: 9.5 %Glenn County9.5Fresno County: 9.5 %Fresno County9.5San Benito County: 9 %San Benito County9Orange County: 9 %Orange County9Siskiyou County: 8.9 %Siskiyou County8.9Inyo County: 8.8 %Inyo County8.8San Diego County: 8.6 %San Diego County8.6Tehama County: 8.6 %Tehama County8.6Stanislaus County: 8.5 %Stanislaus County8.5Calaveras County: 8.4 %Calaveras County8.4San Joaquin County: 8.3 %San Joaquin County8.3Amador County: 8.3 %Amador County8.3Sutter County: 8.3 %Sutter County8.3Yuba County: 8.1 %Yuba County8.1San Luis Obispo County: 8.1 %San Luis Obispo County8.1Lake County: 8 %Lake County8Tuolumne County: 8 %Tuolumne County8Butte County: 7.7 %Butte County7.7Nevada County: 7.7 %Nevada County7.7Shasta County: 7.7 %Shasta County7.7Del Norte County: 7.7 %Del Norte County7.7Sonoma County: 7.7 %Sonoma County7.7Lassen County: 7.6 %Lassen County7.6Humboldt County: 7.6 %Humboldt County7.6Napa County: 7.3 %Napa County7.3Santa Cruz County: 7.2 %Santa Cruz County7.2Sierra County: 7 %Sierra County7Sacramento County: 6.3 %Sacramento County6.3Alpine County: 6.1 %Alpine County6.1Yolo County: 5.9 %Yolo County5.9Solano County: 5.7 %Solano County5.7Contra Costa County: 5.7 %Contra Costa County5.7El Dorado County: 4.9 %El Dorado County4.9Santa Clara County: 4.9 %Santa Clara County4.9Marin County: 4.9 %Marin County4.9Alameda County: 4.7 %Alameda County4.7San Mateo County: 4.5 %San Mateo County4.5San Francisco County: 4.2 %San Francisco County4.2Placer County: 3.7 %Placer County3.7
%. Source: Invokely calculation with data from U.S. Census Bureau. Retrieved 2026-10-12.

Full ranking

RankCounties2023 (%)Change on 2022
1Trinity County16.9-0.7 pts
2Mono County14.7-3.4 pts
3Santa Barbara County14.2-0.2 pts
4Monterey County13.9-0.3 pts
5Colusa County12.7+1.3 pts
6Merced County12.3+0.3 pts
7Tulare County12.2+0.3 pts
8Mendocino County11.9-1.3 pts
9Los Angeles County11.5-0.4 pts
10San Bernardino County11.4-0.2 pts
11Kern County11.3+0.1 pts
12Imperial County11.2+1 pts
13Modoc County11.2+3.5 pts
14Ventura County11-0.4 pts
15Riverside County10.90 pts
16Mariposa County10.9-1.7 pts
17Madera County10.8+0.2 pts
18Kings County9.7+0.4 pts
19Plumas County9.6+1.6 pts
20Glenn County9.5-1.9 pts
21Fresno County9.5-0.1 pts
22San Benito County9+0.4 pts
23Orange County9-0.1 pts
24Siskiyou County8.9-0.9 pts
25Inyo County8.8+0.6 pts
26San Diego County8.6-0.5 pts
26Tehama County8.60 pts
28Stanislaus County8.5+0.1 pts
29Calaveras County8.4-1.1 pts
30San Joaquin County8.3-0.3 pts
31Amador County8.3+0.7 pts
32Sutter County8.3-0.2 pts
33Yuba County8.1-0.8 pts
34San Luis Obispo County8.1+0.1 pts
35Lake County8-0.7 pts
36Tuolumne County8+0.3 pts
37Butte County7.7-0.7 pts
38Nevada County7.7-0.6 pts
38Shasta County7.70 pts
40Del Norte County7.7+1.2 pts
40Sonoma County7.70 pts
42Lassen County7.6-1.4 pts
43Humboldt County7.6-0.7 pts
44Napa County7.3-0.1 pts
45Santa Cruz County7.20 pts
46Sierra County7+2.8 pts
47Sacramento County6.3-0 pts
48Alpine County6.1-3.8 pts
49Yolo County5.9-0.2 pts
50Solano County5.70 pts
51Contra Costa County5.7+0.4 pts
52El Dorado County4.9-0.1 pts
53Santa Clara County4.9-0 pts
54Marin County4.9+0.2 pts
55Alameda County4.70 pts
56San Mateo County4.5+0.2 pts
57San Francisco County4.2-0.2 pts
58Placer County3.7-0 pts

Other periods

About this ranking

People aged 35 to 64 without health insurance coverage of any kind, as a percentage of the civilian noninstitutionalized population aged 35 to 64. United States: American Community Survey five-year estimate, where the period shown is the last year of the five-year span.

Coverage is what people reported at the interview, so the five-year figure averages five years of answers. People whose only coverage is the Indian Health Service count as uninsured. Active-duty military and people living in institutions are outside the universe. For single-year model-based county figures under 65, see uninsured_rate_under_65, uninsured_rate_18_64 and uninsured_rate_under_19 (SAHIE), a different source.

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 B27010: people aged 35 to 64 with no health insurance coverage as a percentage of the civilian noninstitutionalized population aged 35 to 64, calculated with stored inputs. https://www2.census.gov/programs-surveys/acs/summary_file/2023/table-based-SF/data/5YRData/acsdt5y2023-b27010.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 B27010: people aged 35 to 64 with no health insurance coverage as a percentage of the civilian noninstitutionalized population aged 35 to 64, calculated with stored inputs (Counties in California by uninsured rate, ages 35 to 64 (US, ACS), 2023) [Data set]. Retrieved October 12, 2026, from https://www2.census.gov/programs-surveys/acs/summary_file/2023/table-based-SF/data/5YRData/acsdt5y2023-b27010.dat

MLA 9

American Community Survey 5-year estimates, table B27010: people aged 35 to 64 with no health insurance coverage as a percentage of the civilian noninstitutionalized population aged 35 to 64, calculated with stored inputs, Counties in California by uninsured rate, ages 35 to 64 (US, ACS), 2023. U.S. Census Bureau, 29 Jan. 2026, https://www2.census.gov/programs-surveys/acs/summary_file/2023/table-based-SF/data/5YRData/acsdt5y2023-b27010.dat. Invokely, https://invokely.ai/rankings/uninsured-rate-ages-35-64/california-counties?period=2023. Accessed 12 Oct. 2026.

Chicago (author-date)

U.S. Census Bureau. 2026. American Community Survey 5-year estimates, table B27010: people aged 35 to 64 with no health insurance coverage as a percentage of the civilian noninstitutionalized population aged 35 to 64, calculated with stored inputs. Counties in California by uninsured rate, ages 35 to 64 (US, ACS), 2023. Dataset. Accessed October 12, 2026. https://www2.census.gov/programs-surveys/acs/summary_file/2023/table-based-SF/data/5YRData/acsdt5y2023-b27010.dat. Also distributed by Invokely, https://invokely.ai/rankings/uninsured-rate-ages-35-64/california-counties?period=2023.

Harvard

U.S. Census Bureau (2026) American Community Survey 5-year estimates, table B27010: people aged 35 to 64 with no health insurance coverage as a percentage of the civilian noninstitutionalized population aged 35 to 64, calculated with stored inputs, Counties in California by uninsured rate, ages 35 to 64 (US, ACS), 2023 [Dataset]. Available at: https://www2.census.gov/programs-surveys/acs/summary_file/2023/table-based-SF/data/5YRData/acsdt5y2023-b27010.dat, via Invokely: https://invokely.ai/rankings/uninsured-rate-ages-35-64/california-counties?period=2023 (Accessed: 12 October 2026).

BibTeX
@misc{census_counties_in_california_by_2023,
  author = {{U.S. Census Bureau}},
  title = {{American Community Survey 5-year estimates, table B27010: people aged 35 to 64 with no health insurance coverage as a percentage of the civilian noninstitutionalized population aged 35 to 64, calculated with stored inputs: Counties in California by uninsured rate, ages 35 to 64 (US, ACS), 2023}},
  year = {2026},
  howpublished = {Data set},
  url = {https://www2.census.gov/programs-surveys/acs/summary_file/2023/table-based-SF/data/5YRData/acsdt5y2023-b27010.dat},
  urldate = {2026-10-12},
  note = {Accessed via Invokely, https://invokely.ai/rankings/uninsured-rate-ages-35-64/california-counties?period=2023. Publisher attribution: U.S. Census Bureau. American Community Survey 5-year estimates, table B27010: people aged 35 to 64 with no health insurance coverage as a percentage of the civilian noninstitutionalized population aged 35 to 64, calculated with stored inputs. https://www2.census.gov/programs-surveys/acs/summary\_file/2023/table-based-SF/data/5YRData/acsdt5y2023-b27010.dat. Retrieved 2026-10-12.},
}
RIS
TY  - DATA
AU  - U.S. Census Bureau
TI  - American Community Survey 5-year estimates, table B27010: people aged 35 to 64 with no health insurance coverage as a percentage of the civilian noninstitutionalized population aged 35 to 64, calculated with stored inputs: Counties in California by uninsured rate, ages 35 to 64 (US, ACS), 2023
PY  - 2026
DA  - 2026/01/29
PB  - U.S. Census Bureau
DB  - Invokely
UR  - https://www2.census.gov/programs-surveys/acs/summary_file/2023/table-based-SF/data/5YRData/acsdt5y2023-b27010.dat
L2  - https://invokely.ai/rankings/uninsured-rate-ages-35-64/california-counties?period=2023
Y2  - 2026/10/12
N1  - Accessed via Invokely, https://invokely.ai/rankings/uninsured-rate-ages-35-64/california-counties?period=2023.
N1  - Publisher attribution: U.S. Census Bureau. American Community Survey 5-year estimates, table B27010: people aged 35 to 64 with no health insurance coverage as a percentage of the civilian noninstitutionalized population aged 35 to 64, calculated with stored inputs. https://www2.census.gov/programs-surveys/acs/summary_file/2023/table-based-SF/data/5YRData/acsdt5y2023-b27010.dat. Retrieved 2026-10-12.
ER  - 
Embed this chart

Paste this code into a web page or a blog post. The chart shows the latest figures as they are published, with the source and a link back to this page.

Sites that read oEmbed links, such as WordPress, can show the chart when you paste the link to this page.

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 uninsured rate, ages 35 to 64 (US, ACS) using official data, and cite the source.
rank_places {"indicator":"uninsured_rate_35_64","level":"province","within":"California","limit":10}
GET https://invokely.ai/api/v1/rank?indicator=uninsured_rate_35_64&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 uninsured rate, ages 35 to 64 (US, ACS)?

Trinity County, with 16.9% in 2023, according to the U.S. Census Bureau.

Which county has the lowest uninsured rate, ages 35 to 64 (US, ACS)?

Placer County, with 3.7% 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, American Community Survey 5-year estimates, table B27010: people aged 35 to 64 with no health insurance coverage as a percentage of the civilian noninstitutionalized population aged 35 to 64, calculated with stored inputs. Retrieved 2026-10-12.

Uninsured rate, ages 35 to 64 (US, ACS): other rankings

Counties in California: more rankings