Counties in Washington by average household size, 2024

Adams County had the highest average household size of 39 counties in 2024, at 3.3 persons per household. Jefferson County had the lowest, at 2 persons per household. The median was 2.4 persons per household and the figure for Washington was 2.5 persons per household. Source: the U.S. Census Bureau.

Highest3.3Adams County

Lowest2Jefferson County

Median2.439 counties

Washington2.5History

All counties, 2024

persons per household. Source: U.S. Census Bureau, American Community Survey 5-year estimates, table B25010: average household size of occupied housing units. Retrieved 2026-10-12.

Full ranking

Rank	Counties	2024 persons per household	Change on 2023
1	Adams County	3.3	+0.6%
2	Franklin County	3.2	-1.5%
3	Yakima County	2.9	-0.7%
4	Grant County	2.8	-1.4%
5	Douglas County	2.7	-0.4%
6	Benton County	2.7	-0.4%
7	Snohomish County	2.6	0%
8	Clark County	2.6	0%
9	Pierce County	2.6	-0.4%
10	Lewis County	2.6	-0.4%
11	Mason County	2.6	-1.2%
12	Cowlitz County	2.5	-0.4%
13	Chelan County	2.5	-1.2%
13	Kitsap County	2.5	-0.8%
15	Thurston County	2.5	-0.8%
16	Skagit County	2.5	-1.2%
16	Stevens County	2.5	-0.8%
18	Skamania County	2.5	0%
19	Spokane County	2.4	-0.4%
19	Walla Walla County	2.4	-0.4%
21	Grays Harbor County	2.4	-1.2%
22	Whatcom County	2.4	-0.8%
23	King County	2.4	0%
24	Lincoln County	2.4	-1.3%
25	Asotin County	2.4	0%
25	Island County	2.4	-0.8%
27	Pend Oreille County	2.3	-0.4%
28	Klickitat County	2.3	+0.4%
28	Okanogan County	2.3	-1.3%
30	Ferry County	2.3	+0.4%
31	Kittitas County	2.3	+4.1%
32	Garfield County	2.3	+3.2%
33	Wahkiakum County	2.2	-1.8%
34	Clallam County	2.2	-1.8%
34	Whitman County	2.2	-4.8%
36	Pacific County	2.2	-0.9%
37	Columbia County	2.1	+2.4%
38	San Juan County	2	+0.5%
39	Jefferson County	2	0%

Other periods

2024
2023
2022
2021

About this ranking

Average number of persons per private household. EU countries: EU-SILC. United States: American Community Survey five-year estimate of people in households divided by occupied housing units, where the period shown is the last year of the five-year span.

Covers private households only; people living in institutions or other group quarters are excluded. EU-SILC figures refer to the survey year. The EU and US surveys differ, so their figures are not strictly comparable.

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 B25010: average household size of occupied housing units. https://www2.census.gov/programs-surveys/acs/summary_file/2024/table-based-SF/data/5YRData/acsdt5y2024-b25010.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 B25010: average household size of occupied housing units (Counties in Washington by average household size, 2024) [Data set]. Retrieved October 12, 2026, from https://www2.census.gov/programs-surveys/acs/summary_file/2024/table-based-SF/data/5YRData/acsdt5y2024-b25010.dat

MLA 9

American Community Survey 5-year estimates, table B25010: average household size of occupied housing units, Counties in Washington by average household size, 2024. U.S. Census Bureau, 29 Jan. 2026, https://www2.census.gov/programs-surveys/acs/summary_file/2024/table-based-SF/data/5YRData/acsdt5y2024-b25010.dat. Invokely, https://invokely.ai/rankings/average-household-size/washington-counties. Accessed 12 Oct. 2026.

Chicago (author-date)

U.S. Census Bureau. 2026. American Community Survey 5-year estimates, table B25010: average household size of occupied housing units. Counties in Washington by average household size, 2024. Dataset. Accessed October 12, 2026. https://www2.census.gov/programs-surveys/acs/summary_file/2024/table-based-SF/data/5YRData/acsdt5y2024-b25010.dat. Also distributed by Invokely, https://invokely.ai/rankings/average-household-size/washington-counties.

Harvard

U.S. Census Bureau (2026) American Community Survey 5-year estimates, table B25010: average household size of occupied housing units, Counties in Washington by average household size, 2024 [Dataset]. Available at: https://www2.census.gov/programs-surveys/acs/summary_file/2024/table-based-SF/data/5YRData/acsdt5y2024-b25010.dat, via Invokely: https://invokely.ai/rankings/average-household-size/washington-counties (Accessed: 12 October 2026).

BibTeX

@misc{census_counties_in_washington_by_2024,
  author = {{U.S. Census Bureau}},
  title = {{American Community Survey 5-year estimates, table B25010: average household size of occupied housing units: Counties in Washington by average household size, 2024}},
  year = {2026},
  howpublished = {Data set},
  url = {https://www2.census.gov/programs-surveys/acs/summary_file/2024/table-based-SF/data/5YRData/acsdt5y2024-b25010.dat},
  urldate = {2026-10-12},
  note = {Accessed via Invokely, https://invokely.ai/rankings/average-household-size/washington-counties. Publisher attribution: U.S. Census Bureau. American Community Survey 5-year estimates, table B25010: average household size of occupied housing units. https://www2.census.gov/programs-surveys/acs/summary\_file/2024/table-based-SF/data/5YRData/acsdt5y2024-b25010.dat. Retrieved 2026-10-12.},
}

RIS

TY  - DATA
AU  - U.S. Census Bureau
TI  - American Community Survey 5-year estimates, table B25010: average household size of occupied housing units: Counties in Washington by average household size, 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-b25010.dat
L2  - https://invokely.ai/rankings/average-household-size/washington-counties
Y2  - 2026/10/12
N1  - Accessed via Invokely, https://invokely.ai/rankings/average-household-size/washington-counties.
N1  - Publisher attribution: U.S. Census Bureau. American Community Survey 5-year estimates, table B25010: average household size of occupied housing units. https://www2.census.gov/programs-surveys/acs/summary_file/2024/table-based-SF/data/5YRData/acsdt5y2024-b25010.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.

Embed code

<iframe src="https://invokely.ai/embed/rankings/average-household-size/washington-counties" width="760" height="500" title="Counties in Washington by average household size, 2024, chart from Invokely" loading="lazy" style="border:0;width:100%;max-width:760px" referrerpolicy="strict-origin-when-cross-origin"></iframe>

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 Washington by average household size using official data, and cite the source.

rank_places {"indicator":"average_household_size","level":"province","within":"Washington","limit":10}
GET https://invokely.ai/api/v1/rank?indicator=average_household_size&level=province&within=Washington&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 average household size?

Adams County, with 3.3 persons per household in 2024, according to the U.S. Census Bureau.

Which county has the lowest average household size?

Jefferson County, with 2 persons per household 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 B25010: average household size of occupied housing units. Retrieved 2026-10-12.