Mercer Island vs SeaTac

A side-by-side comparison of Mercer Island and SeaTac: population, income, housing, and more.

Mercer Island and SeaTac are places in Washington. This page compares them across population, income, housing, education, commuting, and how each has changed since 2019.

SeaTac has the higher population (31,143 vs 25,282 in Mercer Island). Mercer Island has the higher median household income ($202,359 vs $76,517 in SeaTac). Mercer Island has the higher median home value ($1,884,200 vs $483,200 in SeaTac).

Population, income & housing

	Mercer Island	SeaTac
Population	25,282	31,143
Median age	45.8 yrs	36.8 yrs
Median household income	$202,359	$76,517
Median home value	$1,884,200	$483,200
Median gross rent	$2,464	$1,637
Housing units	10,454	12,424
Homeownership rate	66.0%	45.1%
Bachelor's degree or higher	78.8%	26.6%
Unemployment rate	2.5%	8.3%

Trends (ACS 5-year, 2019–2023)

	Mercer Island	SeaTac
Population	25,675 → 25,282 (-1.5%)	29,019 → 31,143 (+7.3%)
Median household income	$147,566 → $202,359 (+37.1%)	$63,009 → $76,517 (+21.4%)
Median home value	$1,218,200 → $1,884,200 (+54.7%)	$321,300 → $483,200 (+50.4%)
Median gross rent	$2,162 → $2,464 (+14.0%)	$1,286 → $1,637 (+27.3%)

Mercer Island

Population

25,67525,282

Median household income

$147,566$202,359

Median home value

$1,218,200$1,884,200

Median gross rent

$2,162$2,464

SeaTac

Population

29,01931,143

Median household income

$63,009$76,517

Median home value

$321,300$483,200

Median gross rent

$1,286$1,637

Age & race/ethnicity

Age distribution (share)

	Mercer Island	SeaTac
Under 5	3.9%	6.0%
5 to 17	18.2%	17.5%
18 to 24	6.0%	7.3%
25 to 34	8.3%	16.2%
35 to 44	12.1%	17.6%
45 to 54	16.8%	10.9%
55 to 64	13.7%	11.2%
65 to 74	9.9%	8.5%
75 and over	11.1%	4.8%

Race & ethnicity (share)

	Mercer Island	SeaTac
White (non-Hispanic)	65.3%	29.3%
Black or African American	1.4%	23.9%
American Indian & Alaska Native	0.0%	0.3%
Asian	22.2%	15.8%
Native Hawaiian & Pacific Islander	0.0%	1.5%
Some other race	0.6%	0.3%
Two or more races	8.2%	6.2%
Hispanic or Latino	2.3%	22.8%

Educational attainment (age 25+)

Share of adults 25+

	Mercer Island	SeaTac
No high school diploma	1.9%	16.1%
High school graduate	5.3%	28.2%
Some college or associate's	14.0%	29.0%
Bachelor's degree	38.3%	20.0%
Graduate or professional degree	40.5%	6.6%

Commute to work

How workers get to work (share)

	Mercer Island	SeaTac
Drove alone	51.6%	60.0%
Carpooled	4.6%	15.7%
Public transit	4.6%	6.9%
Walked	1.6%	4.3%
Bicycle	0.2%	0.0%
Worked from home	35.7%	10.8%
Other means	1.7%	2.2%

Housing

Units in structure (share)

	Mercer Island	SeaTac
1-unit, detached	65.6%	43.7%
1-unit, attached	0.4%	2.7%
2 to 4 units	1.0%	6.8%
5 to 19 units	8.0%	22.1%
20 or more units	24.2%	19.5%
Mobile home & other	0.8%	5.2%

Poverty & households

	Mercer Island	SeaTac
Poverty rate	4.6%	10.4%
Average household size	2.54	2.57
Mean commute (minutes)	25	26
Median year structure built	1973	1971