Counties in California by uninsured rate, all ages (US), 2024

Sierra County had the highest uninsured rate, all ages (US) of 58 counties in 2024, at 13.7%. Placer County had the lowest, at 3.2%. The median was 6.3% and the figure for California was 6.6%. Source: the U.S. Census Bureau.

Keep it in a collection in your library.
Highest13.7Sierra County
Lowest3.2Placer County
Median6.358 counties
California6.6History

Map of counties, 2024

Alameda County: 4 %Alpine County: 3.7 %Amador County: 4.9 %Butte County: 6.4 %Calaveras County: 5 %Colusa County: 8 %Contra Costa County: 4.6 %Del Norte County: 5.5 %El Dorado County: 3.9 %Fresno County: 6.7 %Glenn County: 8.5 %Humboldt County: 4.9 %Imperial County: 6 %Inyo County: 7 %Kern County: 7.8 %Kings County: 7.3 %Lake County: 6.9 %Lassen County: 6.4 %Los Angeles County: 8.2 %Madera County: 7.4 %Marin County: 3.8 %Mariposa County: 5.2 %Mendocino County: 7.7 %Merced County: 8.1 %Modoc County: 10 %Mono County: 8.8 %Monterey County: 9.6 %Napa County: 5.7 %Nevada County: 5.3 %Orange County: 6.4 %Placer County: 3.2 %Plumas County: 5.8 %Riverside County: 7.7 %Sacramento County: 4.9 %San Benito County: 6 %San Bernardino County: 8 %San Diego County: 6.4 %San Francisco County: 3.3 %San Joaquin County: 6.3 %San Luis Obispo County: 5.7 %San Mateo County: 3.8 %Santa Barbara County: 8.7 %Santa Clara County: 3.9 %Santa Cruz County: 4.9 %Shasta County: 6.5 %Sierra County: 13.7 %Siskiyou County: 6 %Solano County: 4.8 %Sonoma County: 5.1 %Stanislaus County: 5.6 %Sutter County: 6.4 %Tehama County: 6.6 %Trinity County: 9.3 %Tulare County: 8.1 %Tuolumne County: 5.3 %Ventura County: 7.3 %Yolo County: 4.8 %Yuba County: 6.5 %
  • Under 4.8
  • 4.8 to 5.3
  • 5.3 to 6.3
  • 6.3 to 6.9
  • 6.9 to 8.1
  • 8.1 and over
%, 2024. Source: Invokely calculation with data from U.S. Census Bureau. Boundaries: U.S. Census Bureau cartographic boundary files.

All counties, 2024

Sierra County: 13.7 %Sierra County13.7Modoc County: 10 %Modoc County10Monterey County: 9.6 %Monterey County9.6Trinity County: 9.3 %Trinity County9.3Mono County: 8.8 %Mono County8.8Santa Barbara County: 8.7 %Santa Barbara County8.7Glenn County: 8.5 %Glenn County8.5Los Angeles County: 8.2 %Los Angeles County8.2Merced County: 8.1 %Merced County8.1Tulare County: 8.1 %Tulare County8.1Colusa County: 8 %Colusa County8San Bernardino County: 8 %San Bernardino County8Kern County: 7.8 %Kern County7.8Riverside County: 7.7 %Riverside County7.7Mendocino County: 7.7 %Mendocino County7.7Madera County: 7.4 %Madera County7.4Kings County: 7.3 %Kings County7.3Ventura County: 7.3 %Ventura County7.3Inyo County: 7 %Inyo County7Lake County: 6.9 %Lake County6.9Fresno County: 6.7 %Fresno County6.7Tehama County: 6.6 %Tehama County6.6Shasta County: 6.5 %Shasta County6.5Yuba County: 6.5 %Yuba County6.5Orange County: 6.4 %Orange County6.4Butte County: 6.4 %Butte County6.4San Diego County: 6.4 %San Diego County6.4Lassen County: 6.4 %Lassen County6.4Sutter County: 6.4 %Sutter County6.4San Joaquin County: 6.3 %San Joaquin County6.3Imperial County: 6 %Imperial County6Siskiyou County: 6 %Siskiyou County6San Benito County: 6 %San Benito County6Plumas County: 5.8 %Plumas County5.8Napa County: 5.7 %Napa County5.7San Luis Obispo County: 5.7 %San Luis Obispo County5.7Stanislaus County: 5.6 %Stanislaus County5.6Del Norte County: 5.5 %Del Norte County5.5Tuolumne County: 5.3 %Tuolumne County5.3Nevada County: 5.3 %Nevada County5.3Mariposa County: 5.2 %Mariposa County5.2Sonoma County: 5.1 %Sonoma County5.1Calaveras County: 5 %Calaveras County5Amador County: 4.9 %Amador County4.9Santa Cruz County: 4.9 %Santa Cruz County4.9Sacramento County: 4.9 %Sacramento County4.9Humboldt County: 4.9 %Humboldt County4.9Yolo County: 4.8 %Yolo County4.8Solano County: 4.8 %Solano County4.8Contra Costa County: 4.6 %Contra Costa County4.6Alameda County: 4 %Alameda County4El Dorado County: 3.9 %El Dorado County3.9Santa Clara County: 3.9 %Santa Clara County3.9San Mateo County: 3.8 %San Mateo County3.8Marin County: 3.8 %Marin County3.8Alpine County: 3.7 %Alpine County3.7San Francisco County: 3.3 %San Francisco County3.3Placer County: 3.2 %Placer County3.2Sierra County: 13.7 %Sierra County13.7Modoc County: 10 %Modoc County10Monterey County: 9.6 %Monterey County9.6Trinity County: 9.3 %Trinity County9.3Mono County: 8.8 %Mono County8.8Santa Barbara County: 8.7 %Santa Barbara County8.7Glenn County: 8.5 %Glenn County8.5Los Angeles County: 8.2 %Los Angeles County8.2Merced County: 8.1 %Merced County8.1Tulare County: 8.1 %Tulare County8.1Colusa County: 8 %Colusa County8San Bernardino County: 8 %San Bernardino County8Kern County: 7.8 %Kern County7.8Riverside County: 7.7 %Riverside County7.7Mendocino County: 7.7 %Mendocino County7.7Madera County: 7.4 %Madera County7.4Kings County: 7.3 %Kings County7.3Ventura County: 7.3 %Ventura County7.3Inyo County: 7 %Inyo County7Lake County: 6.9 %Lake County6.9Fresno County: 6.7 %Fresno County6.7Tehama County: 6.6 %Tehama County6.6Shasta County: 6.5 %Shasta County6.5Yuba County: 6.5 %Yuba County6.5Orange County: 6.4 %Orange County6.4Butte County: 6.4 %Butte County6.4San Diego County: 6.4 %San Diego County6.4Lassen County: 6.4 %Lassen County6.4Sutter County: 6.4 %Sutter County6.4San Joaquin County: 6.3 %San Joaquin County6.3Imperial County: 6 %Imperial County6Siskiyou County: 6 %Siskiyou County6San Benito County: 6 %San Benito County6Plumas County: 5.8 %Plumas County5.8Napa County: 5.7 %Napa County5.7San Luis Obispo County: 5.7 %San Luis Obispo County5.7Stanislaus County: 5.6 %Stanislaus County5.6Del Norte County: 5.5 %Del Norte County5.5Tuolumne County: 5.3 %Tuolumne County5.3Nevada County: 5.3 %Nevada County5.3Mariposa County: 5.2 %Mariposa County5.2Sonoma County: 5.1 %Sonoma County5.1Calaveras County: 5 %Calaveras County5Amador County: 4.9 %Amador County4.9Santa Cruz County: 4.9 %Santa Cruz County4.9Sacramento County: 4.9 %Sacramento County4.9Humboldt County: 4.9 %Humboldt County4.9Yolo County: 4.8 %Yolo County4.8Solano County: 4.8 %Solano County4.8Contra Costa County: 4.6 %Contra Costa County4.6Alameda County: 4 %Alameda County4El Dorado County: 3.9 %El Dorado County3.9Santa Clara County: 3.9 %Santa Clara County3.9San Mateo County: 3.8 %San Mateo County3.8Marin County: 3.8 %Marin County3.8Alpine County: 3.7 %Alpine County3.7San Francisco County: 3.3 %San Francisco County3.3Placer County: 3.2 %Placer County3.2
%. Source: Invokely calculation with data from U.S. Census Bureau. Retrieved 2026-10-12.

Full ranking

RankCounties2024 (%)Change on 2023
1Sierra County13.7+1.3 pts
2Modoc County10+0.1 pts
3Monterey County9.6-0.4 pts
4Trinity County9.3-3.1 pts
5Mono County8.8-2.8 pts
6Santa Barbara County8.7-0.5 pts
7Glenn County8.5-0.4 pts
8Los Angeles County8.2-0.5 pts
9Merced County8.1-0.8 pts
10Tulare County8.1+0.1 pts
11Colusa County8-0.9 pts
12San Bernardino County8-0.4 pts
13Kern County7.8-0 pts
14Riverside County7.7-0.3 pts
15Mendocino County7.7-0.5 pts
16Madera County7.4-0.2 pts
17Kings County7.3-0.6 pts
18Ventura County7.3-0.7 pts
19Inyo County7-0.2 pts
20Lake County6.9+0.5 pts
21Fresno County6.7-0.4 pts
22Tehama County6.6+0.2 pts
23Shasta County6.5-0.2 pts
24Yuba County6.5-0.4 pts
25Orange County6.4-0.4 pts
26Butte County6.4+0.1 pts
26San Diego County6.4-0.4 pts
28Lassen County6.4-0.3 pts
28Sutter County6.4+0.4 pts
30San Joaquin County6.3-0.2 pts
31Imperial County6-0.8 pts
32Siskiyou County6-0.4 pts
33San Benito County6-0.3 pts
34Plumas County5.8+0.8 pts
35Napa County5.70 pts
36San Luis Obispo County5.7-0.1 pts
37Stanislaus County5.6-0.4 pts
38Del Norte County5.5-0.4 pts
39Tuolumne County5.3-0.5 pts
40Nevada County5.30 pts
41Mariposa County5.2-1.3 pts
42Sonoma County5.1-0.3 pts
43Calaveras County5-0.2 pts
44Amador County4.9-1 pts
44Santa Cruz County4.9-0.4 pts
46Sacramento County4.9-0.3 pts
47Humboldt County4.9-0.9 pts
48Yolo County4.8+0.2 pts
49Solano County4.8-0 pts
50Contra Costa County4.6-0.2 pts
51Alameda County4-0.1 pts
52El Dorado County3.9-0.1 pts
52Santa Clara County3.9-0.1 pts
54San Mateo County3.8-0.1 pts
55Marin County3.8-0 pts
56Alpine County3.7-1.4 pts
57San Francisco County3.3-0.2 pts
58Placer County3.2-0.2 pts

Other periods

About this ranking

People without health insurance coverage of any kind, as a percentage of the civilian noninstitutionalized population. 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 with no health insurance coverage as a percentage of the civilian noninstitutionalized population, calculated with stored inputs. https://www2.census.gov/programs-surveys/acs/summary_file/2024/table-based-SF/data/5YRData/acsdt5y2024-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 with no health insurance coverage as a percentage of the civilian noninstitutionalized population, calculated with stored inputs (Counties in California by uninsured rate, all ages (US), 2024) [Data set]. Retrieved October 12, 2026, from https://www2.census.gov/programs-surveys/acs/summary_file/2024/table-based-SF/data/5YRData/acsdt5y2024-b27010.dat

MLA 9

American Community Survey 5-year estimates, table B27010: people with no health insurance coverage as a percentage of the civilian noninstitutionalized population, calculated with stored inputs, Counties in California by uninsured rate, all ages (US), 2024. U.S. Census Bureau, 29 Jan. 2026, https://www2.census.gov/programs-surveys/acs/summary_file/2024/table-based-SF/data/5YRData/acsdt5y2024-b27010.dat. Invokely, https://invokely.ai/rankings/uninsured-rate/california-counties. Accessed 12 Oct. 2026.

Chicago (author-date)

U.S. Census Bureau. 2026. American Community Survey 5-year estimates, table B27010: people with no health insurance coverage as a percentage of the civilian noninstitutionalized population, calculated with stored inputs. Counties in California by uninsured rate, all ages (US), 2024. Dataset. Accessed October 12, 2026. https://www2.census.gov/programs-surveys/acs/summary_file/2024/table-based-SF/data/5YRData/acsdt5y2024-b27010.dat. Also distributed by Invokely, https://invokely.ai/rankings/uninsured-rate/california-counties.

Harvard

U.S. Census Bureau (2026) American Community Survey 5-year estimates, table B27010: people with no health insurance coverage as a percentage of the civilian noninstitutionalized population, calculated with stored inputs, Counties in California by uninsured rate, all ages (US), 2024 [Dataset]. Available at: https://www2.census.gov/programs-surveys/acs/summary_file/2024/table-based-SF/data/5YRData/acsdt5y2024-b27010.dat, via Invokely: https://invokely.ai/rankings/uninsured-rate/california-counties (Accessed: 12 October 2026).

BibTeX
@misc{census_counties_in_california_by_2024,
  author = {{U.S. Census Bureau}},
  title = {{American Community Survey 5-year estimates, table B27010: people with no health insurance coverage as a percentage of the civilian noninstitutionalized population, calculated with stored inputs: Counties in California by uninsured rate, all ages (US), 2024}},
  year = {2026},
  howpublished = {Data set},
  url = {https://www2.census.gov/programs-surveys/acs/summary_file/2024/table-based-SF/data/5YRData/acsdt5y2024-b27010.dat},
  urldate = {2026-10-12},
  note = {Accessed via Invokely, https://invokely.ai/rankings/uninsured-rate/california-counties. Publisher attribution: U.S. Census Bureau. American Community Survey 5-year estimates, table B27010: people with no health insurance coverage as a percentage of the civilian noninstitutionalized population, calculated with stored inputs. https://www2.census.gov/programs-surveys/acs/summary\_file/2024/table-based-SF/data/5YRData/acsdt5y2024-b27010.dat. Retrieved 2026-10-12.},
}
RIS
TY  - DATA
AU  - U.S. Census Bureau
TI  - American Community Survey 5-year estimates, table B27010: people with no health insurance coverage as a percentage of the civilian noninstitutionalized population, calculated with stored inputs: Counties in California by uninsured rate, all ages (US), 2024
PY  - 2026
DA  - 2026/01/29
PB  - U.S. Census Bureau
DB  - Invokely
UR  - https://www2.census.gov/programs-surveys/acs/summary_file/2024/table-based-SF/data/5YRData/acsdt5y2024-b27010.dat
L2  - https://invokely.ai/rankings/uninsured-rate/california-counties
Y2  - 2026/10/12
N1  - Accessed via Invokely, https://invokely.ai/rankings/uninsured-rate/california-counties.
N1  - Publisher attribution: U.S. Census Bureau. American Community Survey 5-year estimates, table B27010: people with no health insurance coverage as a percentage of the civilian noninstitutionalized population, calculated with stored inputs. https://www2.census.gov/programs-surveys/acs/summary_file/2024/table-based-SF/data/5YRData/acsdt5y2024-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, all ages (US) using official data, and cite the source.
rank_places {"indicator":"uninsured_rate","level":"province","within":"California","limit":10}
GET https://invokely.ai/api/v1/rank?indicator=uninsured_rate&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, all ages (US)?

Sierra County, with 13.7% in 2024, according to the U.S. Census Bureau.

Which county has the lowest uninsured rate, all ages (US)?

Placer County, with 3.2% 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 B27010: people with no health insurance coverage as a percentage of the civilian noninstitutionalized population, calculated with stored inputs. Retrieved 2026-10-12.

Uninsured rate, all ages (US): other rankings

Counties in California: more rankings