The Town FilesMercer Island, Washington
City in King County · population 25,748 (2020 Census)
- Median home
- $2,000,001
- Household income
- $219,069
- Jan low / Jul high
- 37° / 77°
- Snow a year
- 4 in
- Tornadoes ≤10 mi since 1950
- 3
- Median age
- 46.4
Mercer Island is a city of 25,748 people in King County, Washington. The median home is worth $2,000,001, above the typical Washington town ($475,000). It ranks more upscale than 99% of Washington towns, better for young professionals than 93% of Washington towns, more walkable than 92% of Washington towns.
How Mercer Island ranks
Percentile among Washington towns with at least 500 people on The Town Files lifestyle rankings. 50 is typical for the state; 90 means better than 90% of Washington towns.
Homes and cost of living
The median home in Mercer Island is worth $2,000,001, above the typical Washington town ($475,000). Homes cost about 9.1 times the median household income of $219,069, which is more affordable than 2% of Washington towns. Median rent is $2,502 a month. 67.0% of households own their home.
| Housing | Mercer Island | Typical Washington town |
|---|---|---|
| Median home value | $2,000,001 | $475,000 |
| Median rent | $2,502 | $1,597 |
| Median household income | $219,069 | $90,625 |
| Home value ÷ income | 9.1× | 5.3× |
| Homeownership | 67.0% | 74.4% |
| Median year built | 1973 | 1985 |
| Seasonal / vacation homes | 0.4% | — |
Who lives in Mercer Island
| People | Mercer Island | Typical Washington town |
|---|---|---|
| Median age | 46.4 | 40.1 |
| Age 65 and over | 22.2% | 17.9% |
| Under 18 | 21.5% | — |
| Bachelor's degree or higher | 81.4% | 27.6% |
| Below the poverty line | 3.8% | 8.5% |
| Veterans | 4.6% | — |
| Born outside the U.S. | 26.4% | — |
| Work from home | 38.6% | 13.4% |
| Average commute | 23.6 min | 27.1 min |
| Homes with broadband | 94.5% | 93.9% |
Weather in Mercer Island
July highs average 77.3°F and January lows 36.8°F. About 36.5 inches of rain and melted snow fall a year, with 3.8 inches of snow (typical Washington town: 4.0 in). Expect about 3 days a year at 90°F or hotter and 30 nights at or below freezing.
Tornadoes, storms and disasters
3 tornadoes have passed within 10 miles of Mercer Island since 1950, compared with 1 for the typical Washington town. 1 rated (E)F2 or stronger. The strongest, an F3, struck on December 12, 1969 about 4.8 miles from the town center. The most recent was on December 12, 1969.
Hail of 1 inch or larger has been reported within 10 miles 2 times; the largest was 1.50 inches on June 8, 1972.
Severe weather in King County since 1996
King County has been included in 35 federal disaster or emergency declarations since 1953, most often for fire, flood, biological.
| Declared | Incident | Declaration |
|---|---|---|
| April 7, 2026 | Flood | DR-4906: Severe Storms, Straight-Line Winds, Flooding, Landslides, And Mudslides |
| December 12, 2025 | Flood | EM-3629: Severe Storms, Straight-Line Winds, Flooding, Landslides, And Mudslides |
| April 28, 2024 | Severe Storm | DR-4775: Severe Winter Storms, Straight-Line Winds, Flooding, Landslides, And Mudslides |
| September 10, 2022 | Fire | FM-5455: Bolt Creek Fire |
| April 23, 2020 | Flood | DR-4539: Severe Storms, Flooding, Landslides, And Mudslides |
Jobs and pay in King County
King County had 1,449,785 jobs in 2024, paying an average of $132,279 a year. Unemployment was 3.4% in 2023; in Mercer Island itself the ACS puts it at 3%.
Public schools in Mercer Island
6 public schools with 3,975 students, about 18.8 students per teacher.
| School | Grades | Students | Per teacher |
|---|---|---|---|
| Mercer Island High School | 9-12 | 1,465 | 19.8 |
| Islander Middle School | 6-8 | 938 | 20.8 |
| West Mercer Elementary | K-5 | 410 | 16.4 |
| Lakeridge Elementary School | K-5 | 403 | 19.2 |
| Northwood Elementary School | PK-5 | 398 | 16.6 |
| Island Park Elementary | K-5 | 361 | 16.4 |
Towns near Mercer Island
- Newcastle, WA3.8 mi · 13,017 people · home $1,205,600
- Bellevue, WA4.2 mi · 151,854 people · home $1,340,300
- Medina, WA4.4 mi · 2,915 people · home $2,000,001
- Clyde Hill, WA4.6 mi · 3,126 people · home $2,000,001
- Bryn Mawr-Skyway, WA4.8 mi · 17,397 people · home $655,200
- Boulevard Park, WA5.2 mi · 4,094 people · home $456,100
- Renton, WA6.1 mi · 106,785 people · home $672,600
- Tukwila, WA6.4 mi · 21,798 people · home $489,000
Mercer Island questions
Is Mercer Island, Washington a good place to retire?
On The Town Files lifestyle rankings, Mercer Island scores better for retirees than 78% of Washington towns and quieter than 23%. 22.2% of residents are 65 or older (median age 46.4).
How much does a house cost in Mercer Island?
The median owner-occupied home in Mercer Island is valued at $2,000,001 (Census ACS 2020–2024), against a median household income of $219,069, so homes cost about 9.1 times income. Median rent is $2,502 a month.
What is the weather like in Mercer Island?
July highs average 77.3°F and January lows 36.8°F (NOAA 1991–2020 normals). It gets about 36.5 inches of precipitation a year and 3.8 inches of snow.
Does Mercer Island get tornadoes?
3 tornadoes have passed within 10 miles of Mercer Island since 1950 (NOAA Storm Events); the strongest was a F3 on December 12, 1969. The typical Washington town has had 1.
- U.S. Census Bureau, American Community Survey 5-year estimates (2020–2024)
- U.S. Census Bureau, 2020 Census and 2025 Gazetteer (2020 / 2025)
- NOAA NCEI U.S. Climate Normals (1991–2020)
- NOAA NCEI Storm Events Database (1950–2026)
- FEMA OpenFEMA Disaster Declarations (this product uses the FEMA OpenFEMA API but is not endorsed by FEMA) (1953–2026)
- NCES Common Core of Data (2023–24)
- BLS Quarterly Census of Employment and Wages; USDA ERS county unemployment (BLS LAUS) (2000–2024)
- The Town Files lifestyle rankings, built from federal demographic, school, crime and housing data (2025)