Jefferson County, Washington Population 2026
Updated April 2026 · US Census ACS 2023 5-Year Estimates · 27th-largest in Washington
The population of Jefferson County, Washington is 33,313 as of the 2023 American Community Survey, making it the 27th-largest county in Washington. The median household income is $71,143, the median home value is $495,100, and the median age is 59.5.
The population of Jefferson County has grown 13.5% since 2010 (29,899 → 33,944), a +0.91% annualized rate.
33,313
Population
+0.91%
Annual growth
18
People / sq mi
$71,143
Median Income
$495,100
Median Home Value
Jefferson County covers 1,804 sq mi of land at 18.5 people per square mile.
About Jefferson County, WA
Jefferson County skews on age — the median resident is 59.5, older than the national median. Jefferson County is a county in Washington with a population of 33,313. It ranks #27 among counties in Washington by population.
Median household income is $71,143, below the US median of $78,538. About 7.7% of residents live below the federal poverty level, below the national 12.4%. Real estate commands a premium here — a median home value of $495,100, with typical rent around $1,291.
The population is unusually well-credentialed for US counties — 43.3% of adults have a four-year degree, above the national 35.0%. Working from home is common here: 21.5% of workers do so, above the national 14.0%, and the average commute runs about 24 minutes each way.
The age structure shapes everything downstream in Jefferson County — from housing demand to the mix of working-age earners reflected in the income figures above.
Jefferson County Population History (2010-2024)
The county of Jefferson County had a population of 29,899 in 2010 and 33,944 in 2024, a 13.5% growth over 14 years. The peak was 33,944 in 2024. Average annual growth rate: 0.91%.
33,944
Population (2024)
29,899
Population (2010)
33,944
Peak (2024)
0.91%
Avg Annual Growth
| Year | Population |
|---|---|
| 2010 | 29,899 |
| 2011 | 29,858 |
| 2012 | 29,808 |
| 2013 | 30,021 |
| 2014 | 30,172 |
| 2015 | 30,376 |
| 2016 | 30,949 |
| 2017 | 31,264 |
| 2018 | 31,864 |
| 2019 | 32,347 |
| 2020 | 33,061 |
| 2021 | 33,558 |
| 2022 | 33,597 |
| 2023 | 33,725 |
| 2024 | 33,944 |
Race & Ethnicity
| White | 86.7% |
| Black or African American | 0.4% |
| Asian | 0.0% |
| Hispanic or Latino (any race) | 4.3% |
| Two or More Races | 0.0% |
Age & Sex
59.5
Median Age
51.2%
Female
48.8%
Male
39.6%
Age 65+
Age Distribution
Children (under 15): 9.5% · Seniors (65+): 39.6%
Income & Poverty
| Median household income | $71,143$-23,809 vs state |
| Mean household income | $101,205 |
| Per-capita income | $49,853 |
| Poverty rate | 7.7%+1.3% vs state |
| Unemployment rate | 3.3% |
| Employment-to-population | 39.6% |
Top Industries by Employment
The largest employment sector in Jefferson County is professional & business services, accounting for 22.6% of workers.
How residents commute
1.5%
Drive alone
4.4%
Carpool
62.1%
Public transit
21.5%
Work from home
23.5 min
Avg commute
Housing
$495,100$-24,700 vs state
Median home value
$1,291
Median rent
79.7%
Homeownership rate
19,359
Total housing units
83.5%
Occupied
16.5%
Vacant
20.3%
Renter-occupied
Social & access
95.9%
With health insurance
94.2%
With broadband internet
54.9%
Foreign-born
12.1%
Veterans (18+)
20.0%
With a disability
92.7%
Speak language other than English at home
Education
96.1%
High School+
43.3%
Bachelor's+
Largest cities in Washington
Other counties in Washington
Part of Washington
Metro areas in Washington
County rankings
Frequently Asked Questions
Jefferson County, Washington has a population of 33,313 according to the US Census Bureau's 2023 American Community Survey 5-year estimates, making it the 27th-largest county in Washington. Population density is 18 people per square mile.
The population of Jefferson County has grown 13.5% since 2010 (29,899 → 33,944), a +0.91% annualized rate.
The median household income in Jefferson County, Washington is $71,143, with mean (average) household income of $101,205 and per-capita income of $49,853. 7.7% of residents live below the federal poverty level.
In Jefferson County, the largest racial and ethnic groups are White (86.7%), Hispanic or Latino (4.3%), Black or African American (0.4%). Figures are from the US Census Bureau's 2023 ACS 5-year estimates and reflect self-reported responses.
The median age in Jefferson County, Washington is 59.5 years. Residents are 51.2% female and 48.8% male.
The median home value in Jefferson County is $495,100 and median monthly rent is $1,291. 79.7% of occupied housing units are owner-occupied. The county has 19,359 total housing units, 16.5% of which are vacant.
The largest employment sector in Jefferson County, Washington is professional, scientific, and management services, employing 22.6% of workers. The unemployment rate is 3.3%.
Seattle is among the largest cities associated with Jefferson County, Washington, with a population of 741,440.
Jefferson County, WA Climate
Jefferson County, WA has an average annual temperature of 4.8°C (41°F) and receives about 2670 mm of precipitation per year. The warmest month is August and the coldest is December. Figures are 1970–2000 climate normals.
4.8°C
Avg Temp
2670
Precip (mm/yr)
Aug
Hottest Month
Dec
Coldest Month
| Month | Avg (°C/°F) | Precip |
|---|---|---|
| January | 0° / 31° | 400 mm |
| February | 1° / 33° | 310 mm |
| March | 1° / 33° | 276 mm |
| April | 2° / 36° | 183 mm |
| May | 5° / 42° | 126 mm |
| June | 8° / 47° | 93 mm |
| July | 11° / 52° | 54 mm |
| August | 12° / 54° | 66 mm |
| September | 10° / 50° | 97 mm |
| October | 6° / 43° | 233 mm |
| November | 2° / 35° | 404 mm |
| December | -1° / 31° | 428 mm |
1970–2000 normals from WorldClim 2.1 (~9 km grid). Precipitation can be less precise near mountains or coastlines, where rainfall varies sharply over short distances.
Best time to visit Jefferson County, WA
The most comfortable months to visit Jefferson County, WA are typically August, July and September, when temperatures are mildest and rainfall is relatively low. The hottest month is August (around 18°C high). The coldest is December (near -3°C low). December is usually the wettest month.
Where to stay near Jefferson County
Visiting or relocating to Jefferson County, WA? Compare hotels and short-term rentals across the county — live availability and prices.
Top-rated places to stay near Jefferson County
Availability and prices from Stay22 partners (Booking.com, Vrbo, Expedia). We may earn a commission from bookings, at no extra cost to you.
Planning a move to Jefferson County?
Get relocation and cost-of-living insights for Jefferson County, WA by email. No spam, unsubscribe anytime.
More from Washington
Population 2,262,713
Population 924,106
Population 834,648
Population 544,323
Full rankings of Washington counties
Statewide data for Washington
Population, race, income, age, and trends across Washington
Data from the American Community Survey (ACS) 5-Year estimates.
Source: U.S. Census Bureau ACS, 2026.