Mercer Island Flag

Mercer Island

County:
King County
County Seat:
No
Area (mi²):
6.383
State:
Washington

Mercer Island is a city located in King County, Washington. Mercer Island has a 2025 population of 25,190 . Mercer Island is currently declining at a rate of -0.44% annually and its population has decreased by -2.17% since the most recent census, which recorded a population of 25,750 in 2020.

The average household income in Mercer Island is $303,425 with a poverty rate of 4.64%. The median age in Mercer Island is 45.8 years: 45.5 years for males, and 46.1 years for females. For every 100 females there are 86.7 males.

25.2K
Total Population
3,947
Density (mi²)
-112 -0.44%
Growth

Mercer Island Population

Mercer Island Population

Data after 2023 is projected based on recent change

Demographics

The racial composition of Mercer Island includes 65.69% White, 22.34% Asian, and smaller percentages for Black or African American, other race, Native American and multiracial populations.

Population by Race

White (65.69%)

Asian (22.34%)

Two or more races (9.66%)

Black or African American (1.44%)

Other race (0.79%)

Native American (0.08%)

Race
Population
Percentage (of total)
White16,60965.69%
Asian5,64922.34%
Two or more races2,4429.66%
Black or African American3631.44%
Other race1990.79%
Native American200.08%

Mercer Island Marital Status

OverallMalesFemales0%10%20%30%40%50%60%70%80%90%100%

Married

Widowed

Divorced

Separated

Never Married

Economics and Income Statistics

Mercer Island's average per capita income is $118,061. Household income levels show a median of $202,359. The poverty rate stands at 4.64%.

Families: A family includes the owner or renter of the home along with everyone related to them - whether through birth, marriage, or adoption. This includes relatives like spouses, children, parents, siblings, grandparents, and any other family members.
Households: A household includes all the people who occupy a housing unit (such as a house or apartment) as their usual place of residence.
Non Families: A nonfamily household is either someone living alone or when the owner/renter lives with people they aren't related to, like roommates.
Name
Median
Mean
Families$250,001$371,886
Married Families$250,001-
Households$202,359$303,425
Non Families$81,951$129,110

$118,061

Average Income

$202,359

Median Household Income

4.64%

Poverty Rate

Nearby Cities

Sources

  1. US Census State Population Estimates - Most recent state estimates from the Census Bureau's Population Estimates Program
  2. US Census County Population Estimates - Most recent county estimates from the Census Bureau's Population Estimates Program
  3. American Community Survey (2009 - 2013)
  4. Census QuickFacts
  5. Historical Populations of States and Counties (1790 - 1990)