King County, Washington Demographics
Population trends, housing costs, income, commuting, and health, all on one page.
King County, WA Population Density Map and Area Scores
Area Score
Health, income and education, each graded from F to A+. Explore interactive maps for deeper analysis.
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A+
Health Top gradeHealthiest county in Washington
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A
Income Above averageWealthiest county in Washington
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A+
Education Top gradeBest educated county in Washington
Source: Map AI Methodology
Population: density and quick facts
| Metric | King County | Washington Avg | U.S. Average |
|---|---|---|---|
| Population | 2,275,758 | 7,801,159 | 337,468,954 |
| Population density (per sq mi) | 986.8 | 109.3 | 86.4 |
| Population growth (%/yr) | 1.17% | 1.21% | 0.59% |
| Median age | 38.6 | 36.2 | 37.3 |
| Households | 936,171 | 3,058,619 | 130,235,071 |
Population in King County grew by 19.9% from 2009 to 2024, reaching 2,275,758 in 2024.
Population Growth 2009–2024
Race & Ethnicity
Age & Sex
The largest generation in King County is Millennials, aged 29–44, at 26.9% of residents. That is 3.5 points above Washington as a whole.
- Gen Z 13–28 483,780 21.3% -0.2 pts
- Millennials 29–44 611,542 26.9% +3.5 pts
- Gen X 45–60 462,565 20.3% +0.8 pts
- Boomers 61–79 316,319 13.9% -2.4 pts
Residents by birth cohort, from the 2025 age distribution. The right-hand figure is how far each cohort's share sits above or below Washington, in percentage points. Children younger than Gen Z and the generations before the Boomers are counted in the population but not shown here, so these shares do not add up to 100%.
Male and female share
Women are 49.5% of the people living in King County and men 50.5%.
- Women 49.5% Washington 49.7%
- Men 50.5% Washington 50.3%
How many residents match a customer profile?
Residents matching this profile
100% of everyone living in King County
Pick an age range and a women/men split and the figure above answers with how many residents that profile reaches.
Economy
King County has a the economy index of A, which means it is very prosperous.
| Metric | King County | Washington Avg | U.S. Average |
|---|---|---|---|
| Median household income | $124,760 | $98,224 | $80,455 |
| Income growth (%/yr) | 5.90% | 5.64% | 4.80% |
| Unemployment rate | 4.8% | 5.0% | 5.2% |
The median household income in King County is about 27% higher than in Washington.
Housing
| Metric | King County | Washington Avg | U.S. Average |
|---|---|---|---|
| Median home price | $833,657 | $485,016 | $248,835 |
| Median rent | $2,092 | $1,759 | $1,407 |
| Homeownership rate | 55.4% | 63.8% | 65.2% |
The median home price in King County is about 33.2 years' worth of rent — buying at the median price costs roughly as much as paying the median rent of $2,092 per month for that long.
Commute Time & Mobility
Commuters in King County spend about 51 minutes on the road round trip each working day. Over a typical 250-day work year, that adds up to roughly 212 hours, about 8.8 full days, spent commuting.
| Metric | King County | Washington Avg | U.S. Average |
|---|---|---|---|
| One-way commute (min) | 25.4 | 22.4 | 22.4 |
| Round-trip commute (min) | 50.9 | 44.8 | 44.8 |
| Yearly time spent (hours) | 212 | 187 | 187 |
| Estimated yearly cost | $6,574 | $5,785 | $5,790 |
| Work from home | 29.1% | 19.8% | 15.0% |
| Highway traffic (vehicles/day) | 17,340 | 10,119 | 8,813 |
| Local road traffic (vehicles/day) | 3,231 | 1,525 | 1,355 |
Fastest commutes among counties in
Washington:
Walla Walla County (12.2 min), San Juan County (12.3 min), Asotin County (13.2 min).
Slowest:
Mason County (32.0 min), Garfield County (28.4 min), Snohomish County (28.3 min).
The average commute time in King County is 25 minutes, longer than the 22 minutes in Washington.
Estimated yearly cost applies a single national wage rule of thumb (U.S. Bureau of Labor Statistics average hourly earnings), not a measurement of wages in this area. Traffic volume figures come from proprietary Ticon and TrafficZoom data.
Education & Households
King County has a education index of A+, which means it is exceptionally educated.
| Metric | King County | Washington Avg | U.S. Average |
|---|---|---|---|
| Bachelor's degree or higher | 51.6% | 35.1% | 31.6% |
| Average household size | 2.38 | 2.50 | 2.53 |
Highest education index among counties in
Washington:
King County (0.4), San Juan County (0.4), Jefferson County (0.4).
Lowest:
Adams County (0.2), Yakima County (0.2), Grant County (0.2).
Health
King County has a health index of A+, which means it is exceptionally healthy.
| Metric | King County | Washington Avg | U.S. Average |
|---|---|---|---|
| Life expectancy (years) | 81.2 | 79.6 | 78.3 |
| Self-rated poor health | 10.1% | 15.4% | 16.3% |
| Smokers | 10.5% | 16.4% | 19.0% |
Highest health index among counties in
Washington:
King County (0.8), Whitman County (0.8), San Juan County (0.8).
Lowest:
Adams County (0.8), Okanogan County (0.8), Pacific County (0.8).
King County, WA Compared With Nearby Counties
King County, WA is the largest of the 6 counties compared here, 2,275,758 residents against a local median of 276,921. The measure that sets King County, WA apart most is median home price: $833,657, 52% above the local median of $550,004.
Median household income tells the same story from another angle: $124,760 against a local median of $99,574, 25% above it. The picture is mixed rather than uniform: median household income runs ahead of the neighbourhood while commute runs behind it, so King County, WA is trading one against the other rather than simply out-performing what surrounds it. The counties themselves spread $211,400 on median home price, so King County, WA sits at one end of an already wide local range rather than apart from it. King County, WA has the highest median home price of the 6 areas compared here.
| Area | Population | Median household income | Median home price | Commute |
|---|---|---|---|---|
| King County, WA | 2,275,758 | $124,760 #1/6 | $833,657 #1/6 | 25.4 min #4/6 |
| Pierce County, WA | 929,755 | $99,574 | $446,511 | 26.9 min |
| Snohomish County, WA | 843,136 | $111,921 | $550,004 | 28.3 min |
| Kitsap County, WA | 276,921 | $104,681 | $617,222 | 21.8 min |
| Skagit County, WA | 131,328 | $88,887 | $412,493 | 21.1 min |
| Island County, WA | 86,836 | $92,129 | $623,893 | 17.5 min |
Frequently Asked Questions
Common questions about King County, Washington.
How big is King County, Washington by population?
About 2,275,758 people live in King County, Washington, in 936,171 households of 2.4 people on average. The median age is 38.6, close to the U.S. median of 37.3.
How densely populated is King County, Washington?
Averaged over its land area, King County, Washington has 987 people per square mile, a density typical of a mix of suburbs, small towns and farmland. That is about 11 times the U.S. average of 86.
How affordable is housing in King County, Washington?
The median home costs 6.7 times the median household income ($833,657 against $124,760), compared with 3.1 times nationally. A ratio of about 3 is traditionally considered affordable. Median rent of $2,092 a month takes about 20% of the median household's income, below the 30% level at which HUD considers renters cost-burdened.
What share of adults in King County, Washington have a college degree?
51.6% of adults in King County, Washington hold a bachelor's degree or higher (about 5 in 10), well above the U.S. share of 31.6%.
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