Census-designated place · Washington
Cottage Lake, Washington
Cottage Lake, census-designated place, in King County, Washington. Cottage Lake had 22,518 people in the ACS 2020-2024 5-year estimates (±1,434). GEOID 5314940.
Residents, 2020-2024
22,518
±1,434 (90% margin)
2020 Census count: 22,857
Median household income
$213,106
±$21,420 (90% margin)
Washington: $98,141
Median home value
$1,230,700
±$48,099 (90% margin)
Washington: $564,600
Median gross rent
$2,740
±$212 (90% margin)
Washington: $1,760
Where is Cottage Lake and what county is it in?
Cottage Lake is a census-designated place: an unincorporated community the Census Bureau draws for counting, with no city government of its own, in King County, Washington. It covers 22.7 square miles of land, 1,005 residents per square mile in 2020.
Cottage Lake is in the Seattle-Tacoma-Bellevue, WA metropolitan statistical area, which takes in 3 counties (Census Bureau delineation, July 2023).
Source: 2024 Gazetteer and 2020 place-by-county files, U.S. Census Bureau · Census reference files
How many people live in Cottage Lake, and is it growing?
The 2020-2024 American Community Survey puts Cottage Lake's population at 22,518 (±1,434). The 2020 Census counted 22,857 residents.
The Census Bureau publishes yearly population estimates for incorporated places only; Cottage Lake is a census-designated place, so its figures come from the ACS and the 2020 Census.
| Measure | Cottage Lake | King County | Change since 2015-2019 |
|---|---|---|---|
| Total population | 22,518 ±1,434 | 2,287,171 | no clear change |
| Households | 7,794 ±425 | 941,054 | no clear change |
| Average household size | 2.88 ±0.10 | 2.39 | no clear change |
| Housing units | 8,040 ±442 | 1,003,284 | no clear change |
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026); Census PEP Vintage 2025 (SUB-EST2025, CO-EST2025); 2020 Census P.L. 94-171 · Check it at data.census.gov
Who lives in Cottage Lake?
The median resident of Cottage Lake is 44.2 years old; 23.8% are under 18 and 18.1% are 65 or older. The largest group is non-Hispanic white residents at 76.4%, then non-Hispanic Asian residents at 10.0%. 17.1% of residents were born outside the United States.
| Measure | Cottage Lake | King County | Change since 2015-2019 |
|---|---|---|---|
| Median age | 44.2 ±1.6 | 37.4 | no clear change |
| Under 18 years | 23.8% ±1.7 pts | 19.5% | – |
| 65 years and over | 18.1% ±2.5 pts | 14.0% | – |
| Male | 52.1% ±1.8 pts | 50.7% | – |
| Hispanic or Latino (any race) | 6.0% ±2.5 pts | 11.0% | +2.8 pts |
| White alone, not Hispanic | 76.4% ±3.1 pts | 52.9% | −6.3 pts |
| Black or African American alone, not Hispanic | 0.2% ±0.2 pts | 6.4% | – |
| Asian alone, not Hispanic | 10.0% ±1.5 pts | 20.5% | no clear change |
| American Indian and Alaska Native alone, not Hispanic | 0.1% ±0.1 pts | 0.4% | – |
| Native Hawaiian and Other Pacific Islander alone, not Hispanic | 0.4% ±0.4 pts | 0.7% | – |
| Two or more races, not Hispanic | 6.7% ±1.7 pts | 7.3% | – |
| Some other race alone, not Hispanic | 0.2% ±0.3 pts | 0.6% | – |
| Born outside the United States | 17.1% ±3.1 pts | 25.8% | +3.6 pts |
| Speak a language other than English at home (age 5+) | 18.1% ±3.8 pts | 31.1% | – |
| Civilian veterans (age 18+) | 3.3% ±0.9 pts | 4.5% | – |
| With a disability | 8.0% ±1.5 pts | 10.3% | – |
| No health insurance coverage | 2.5% ±1.4 pts | 5.2% | no clear change |
| High school graduate or higher (age 25+) | 96.9% ±1.4 pts | 93.8% | – |
| Bachelor's degree or higher (age 25+) | 67.8% ±3.7 pts | 56.7% | no clear change |
| Graduate or professional degree (age 25+) | 26.8% ±3.4 pts | 24.2% | – |
| Lived in the same house a year earlier | 94.0% ±1.8 pts | 83.3% | – |
| Moved from another state in the past year | 0.6% ±0.5 pts | 3.5% | – |
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026) (Data Profiles DP02, DP05) · Check it at data.census.gov
What do households in Cottage Lake earn?
Half of Cottage Lake's 7,794 households earn less than $213,106 a year (±$21,420), against $124,746 in King County and $98,141 in Washington. In 2015-2019 it was $198,428 in 2024 dollars; the margins of error cannot tell the two periods apart. 3.2% of residents live below the poverty line.
| Measure | Cottage Lake | King County | Change since 2015-2019 |
|---|---|---|---|
| Median household income | $213,106 ±$21,420 | $124,746 | no clear change |
| Mean household income | $268,066 ±$19,808 | $176,799 | – |
| Per capita income | $93,328 ±$7,105 | $74,100 | no clear change |
| People below the poverty line | 3.2% ±1.3 pts | 8.6% | +1.5 pts |
| Children under 18 below the poverty line | 2.0% ±1.8 pts | 9.7% | – |
| Households receiving SNAP | 3.0% ±1.3 pts | 8.2% | – |
| Households with a computer | 99.6% ±0.5 pts | 98.1% | – |
| Households with a broadband subscription | 98.8% ±0.9 pts | 95.1% | – |
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026) (Data Profile DP03) · Check it at data.census.gov
What does housing cost in Cottage Lake?
Owners occupy 91.1% of Cottage Lake's occupied homes and renters 8.9%. The median owner-occupied home is valued at $1,230,700 by its owner (±$48,099). The median renter pays $2,740 a month including utilities, and 40.8% of renters pay 35% or more of their income on rent.
| Measure | Cottage Lake | King County | Change since 2015-2019 |
|---|---|---|---|
| Median home value (owner-occupied) | $1,230,700 ±$48,099 | $859,900 | +$248,360 |
| Median gross rent | $2,740 ±$212 | $2,092 | no clear change |
| Renters paying 35% or more of income on rent | 40.8% ±20.3 pts | 37.5% | no clear change |
| Median monthly owner costs, with a mortgage | $3,744 ±$232 | $3,273 | – |
| Owner-occupied homes | 91.1% ±2.8 pts | 55.4% | no clear change |
| Renter-occupied homes | 8.9% ±2.8 pts | 44.6% | – |
| Housing units | 8,040 ±442 | 1,003,284 | no clear change |
| Homeowner vacancy rate | 0.0% ±0.6 pts | 0.7% | – |
| Rental vacancy rate | 0.0% ±5.4 pts | 5.3% | – |
| Single-family detached homes | 97.0% ±1.5 pts | 50.0% | – |
| Mobile homes | 1.4% ±1.2 pts | 1.4% | – |
| Built 2020 or later | 0.9% ±1.1 pts | 2.1% | – |
| Built 2010 to 2019 | 2.3% ±1.1 pts | 14.2% | – |
| Built 1939 or earlier | 1.6% ±1.1 pts | 10.9% | – |
| Households with no vehicle | 0.9% ±0.6 pts | 11.2% | – |
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026) (Data Profile DP04) · Check it at data.census.gov
How do people in Cottage Lake work and get to work?
57.4% of Cottage Lake's workers drive alone and 33.8% work from home. The average trip to work takes 25.9 minutes. The unemployment rate in 2020-2024 averaged 4.1%.
| Measure | Cottage Lake | King County | Change since 2015-2019 |
|---|---|---|---|
| In the labor force (age 16+) | 59.6% ±3.6 pts | 69.9% | – |
| Unemployment rate | 4.1% ±1.9 pts | 4.8% | no clear change |
| Drove alone to work | 57.4% ±3.9 pts | 50.4% | – |
| Carpooled | 6.0% ±1.8 pts | 7.0% | – |
| Public transportation | 0.8% ±0.6 pts | 6.8% | – |
| Walked | 0.6% ±0.6 pts | 4.3% | – |
| Worked from home | 33.8% ±3.6 pts | 29.2% | +21.5 pts |
| Mean travel time to work | 25.9 min ±1.5 | 27.6 min | −6.4 min |
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026) (Data Profile DP03) · Check it at data.census.gov
What census tracts are in Cottage Lake?
5 census tracts lie mostly in Cottage Lake, and 3 more reach into it (2020 census blocks). Their median household incomes run from $159,181 (Tract 323.07) to $250,000 or more (Tract 323.20).
| Tract | Residents, 2020-2024 | Median household income |
|---|---|---|
| Tract 323.07King County | 6,396 | $159,181 |
| Tract 323.11King County | 5,925 | $218,382 |
| Tract 323.22King County | 2,980 | $240,000 |
| Tract 323.20King County | 4,474 | $250,000 or more |
| Tract 323.21King County | 6,925 | $250,000 or more |
| Tract 323.26King County | 4,080 | $228,083 |
| Tract 323.19King County | 7,011 | $120,357 |
| Tract 323.27King County | 4,036 | $158,929 |
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026); 2020 block assignment files (tract share = share of the tract's census blocks in Cottage Lake) · Census block assignment files
How does Cottage Lake compare with other places in Washington?
Cottage Lake ranks 8th of 387 places in Washington with 1,000 or more residents and a reliable estimate, by median household income.
| Measure | Rank | Of |
|---|---|---|
| Population (ACS 2020-2024) | 62nd | 393 |
| Residents per square mile | 260th | 394 |
| Median household income | 8th | 387 |
| Per capita income | 14th | 393 |
| Median home value | 8th | 384 |
| Median gross rent | 14th | 351 |
| Poverty rate | 270th | 281 |
| Bachelor's degree or higher | 16th | 382 |
| Median age | 112th | 394 |
| Owner-occupied share | 43rd | 388 |
| Work from home | 26th | 307 |
| Travel time to work | 217th | 394 |
Cottage Lake's figures with every place in Washington (CSV)
Every place in Washington, sortable · Compare Cottage Lake with other places
Source: PlainCities ranks computed from the American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026) and PEP Vintage 2025 · How ranks are computed
How reliable are the figures for Cottage Lake?
14 of the 57 figures for Cottage Lake on this page carry a coefficient of variation over 40% and are marked with a ring: they come from a small sample, so read them as rough.
The American Community Survey samples about one household in eight over five years, so every figure is an estimate with a 90% margin of error (shown under each value). A ring marks an estimate whose coefficient of variation is over 40%. A change is called only when the gap between the two periods is larger than their combined 90% margin (the square root of the sum of the two squared margins), the Census Bureau's test. How to read a margin of error.
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026): margins of error as published · ACS technical documentation
How these figures are made: methodology and release checks · reading a margin of error · every state · corrections
Not on this page: crime, weather and schools for Cottage Lake are other agencies' records. Crime: the FBI's Crime Data Explorer · climate: NOAA's U.S. Climate Normals · schools: the National Center for Education Statistics' school search.