Mercer Island, WA · standard
ZIP Code 98040
King County, Washington - Census ACS demographics, housing tenure, and business patterns, benchmarked against every US ZIP.
- 22,699
- 1,373/sq mi High-density area
- $219,069
- Median income Above-median income area
- $2,000,000+
- Median home value Above-median home value
- 81.4%
- Bachelor's or higher Above-average bachelor's attainment
National ZIP placement
Mercer Island pairs a top-decile household income with top-decile home values, in a low-density, homeowner-dominated area.
- Top 1%
- household income, US ZIPs
- Top 1%
- home value, US ZIPs
- 1,373
- people per sq mi
- 67%
- owner-occupied homes
Source: U.S. Census Bureau ACS 5-Year Estimates (2019–2023). Percentiles rank ZIP 98040 against every reporting US ZIP.
ZIP code 98040 is a densely settled ZIP (a standard USPS delivery area) in Mercer Island, King County, Washington, with 22,699 residents across 16.5 square miles, a density of 1,373 people per square mile, in the Los Angeles time zone.
ZIP 98040 skews affluent, with a median household income of $219,069 (141% above the average Washington ZIP), while per-capita income is $128,615. Both reported hardship measures are comparatively low in absolute terms: poverty is 3.8% and unemployment is 3.0%. Housing is both higher-cost and owner-heavy: median home value is $2,000,000+ (291% above the average Washington ZIP), while 67.0% of occupied homes are owner-occupied and median rent is $2,502.
This is a highly-educated ZIP: 81.4% of adults hold a bachelor's degree or higher, the median age is 46.4, and the average commute is 24 minutes. The page also surfaces 10 ZIP codes within roughly 10 miles and 6 more in King County, so 98040 can be compared with both its immediate and county-level context.
Every figure on this page is sourced from the U.S. Census Bureau American Community Survey 5-Year Estimates (including median rent) and the FHFA House Price Index, no estimates, no proprietary scoring. Verify with Census →
Top industries in ZIP 98040
Top 5 sectors by establishment count in Mercer Island, WA
Which industries have the most business establishments in ZIP 98040.
- Professional, scientific, and technical services
Professional, scientific, and technical services
182 establishments
- Real estate and rental and leasing
Real estate and rental and leasing
115 establishments
- Health care and social assistance
Health care and social assistance
108 establishments
- Finance and insurance
Finance and insurance
81 establishments
- Other services (except public administration) 63
Other services (except public administration)
63 establishments
What this shows Establishment counts come from the Census ZIP Code Business Patterns program, which counts physical business locations rather than employees or revenue.
Source: U.S. Census Bureau, American Community Survey 5-Year Estimates + ZIP Code Business Patterns + FHFA HPI ACS demographics and median rent, ZBP business establishments, FHFA HPI for ZIP 98040, Mercer Island, WA · 2023 Census ACS 5-Year Estimates use a rolling 60-month sample for stable small-geography estimates; ZBP updated annually; FHFA HPI updated quarterly/annually.
Quick Facts
22,699
Population
16.5
Area (sq mi)
1,373
People / sq mi
Los Angeles
Time Zone
standard
ZIP Type
Who lives in ZIP 98040?
46.4
Median Age
47.6%
Male
52.4%
Female
26.4%
Foreign-Born
Hispanic or Latino is an ethnicity category from the Census Bureau and may overlap with other categories above.
Source: U.S. Census Bureau, ACS 5-Year Estimates (2023)
How much do residents earn?
$219,069
Median Household Income
+141% vs state ZIP avg
$128,615
Per Capita Income
3.8%
Poverty Rate
3.0%
Unemployment Rate
23.6 min
Mean Commute Time
How ZIP 98040 ranks among Washington ZIPs
Mercer Island, WA household income vs. every Washington ZIP code
Median household income among 547 reporting Washington ZIPs (this ZIP's population is too small for a reliable national-corpus placement)
$219,069 Top 1% higher than 99% of 547 Washington ZIPs
Each bar is a $20K-wide band; taller bars hold more Washington ZIPs. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count, share, and where it sits relative to this entry.
Source U.S. Census Bureau, ACS 5-Year Estimates · 2019–2023
Source: U.S. Census Bureau, ACS 5-Year Estimates (2023)
What is the education profile here?
Source: U.S. Census Bureau, ACS 5-Year Estimates (2023)
What does housing look like?
Housing stock: occupied vs vacant
10,609housing units
10,609
Total Housing Units
10,068
Occupied Units
541
Vacant Units
2.50
Avg Household Size
Occupancy Type
$2,000,000+
Median Home Value
+291% vs state ZIP avg
$2,502
Median Rent
1973
Median Year Built
Source: U.S. Census Bureau, ACS 5-Year Estimates (2023)
How have home values changed over time?
FHFA House Price Index, annual appreciation data based on repeat sales and appraisals
+32.6%
YoY Change (2023)
290
HPI Index (2000 = 100)
+190%
Total Change Since 2000
Home values in ZIP 98040 have increased 32.6% over the past year (2023). Since 2000, this ZIP has seen +190% cumulative appreciation.
| Year | Annual Change | HPI Index |
|---|---|---|
| 2019 | -5.6% | 240 |
| 2020 | -5.2% | 227 |
| 2021 | +1.6% | 231 |
| 2022 | -5.4% | 218 |
| 2023 | +32.6% | 290 |
Source: Federal Housing Finance Agency (FHFA) House Price Index, All-Transactions, Five-Digit ZIP Codes (Developmental Index). Index base = 100 in year 2000. Data through 2023. ZIP codes with few transactions may show missing values.
What businesses operate in this ZIP?
Census Bureau data shows 830 business establishments in ZIP 98040, employing approximately 7,524 people with a combined annual payroll of $466,919,000.
830
Businesses
7,524
Employees
$466.9M
Annual Payroll
16
Industry Sectors
| Industry | Establishments | % of Total |
|---|---|---|
| Professional, scientific, and technical services | 182 | 21.9% |
| Real estate and rental and leasing | 115 | 13.9% |
| Health care and social assistance | 108 | 13.0% |
| Finance and insurance | 81 | 9.8% |
| Other services (except public administration) | 63 | 7.6% |
| Construction | 53 | 6.4% |
| Accommodation and food services | 42 | 5.1% |
| Retail trade | 35 | 4.2% |
| Administrative and support and waste management and remediation services | 35 | 4.2% |
| Wholesale trade | 31 | 3.7% |
| Educational services | 29 | 3.5% |
| Arts, entertainment, and recreation | 26 | 3.1% |
| Information | 19 | 2.3% |
| Transportation and warehousing | 4 | 0.5% |
| Management of companies and enterprises | 4 | 0.5% |
| Manufacturing | 3 | 0.4% |
Source: U.S. Census Bureau, ZIP Code Business Patterns (ZBP), 2023. Employment figures may include noise for disclosure avoidance.
Nearby ZIP Codes
Want a side-by-side? Compare 98040 vs 98118 →
ZIP 98040 vs its nearest neighbors, by population
Resident population of this ZIP and the closest reporting ZIP codes within ~10 miles.
- 98118
Seattle (98118)
42,731 residents
- 98006
Bellevue (98006)
36,364 residents
- 98056
Renton (98056)
32,489 residents
- 98122
Seattle (98122)
31,454 residents
- 98004
Bellevue (98004)
27,946 residents
- 98144
Seattle (98144)
26,881 residents
- 98178
Seattle (98178)
24,092 residents
- 98040
Mercer Island (98040)
22,699 residents
- 98108
Seattle (98108)
22,374 residents
What this shows Among its immediate neighbors, ZIP 98040 ranks #8 by population - useful context the national average alone can't give.
ZIP 98040 vs its nearest neighbors, by median income
Median household income of this ZIP and the closest reporting ZIP codes within ~10 miles.
- 98039
Medina (98039)
$250,000 median income
- 98040
Mercer Island (98040)
$219,069 median income
- 98006
Bellevue (98006)
$198,150 median income
- 98004
Bellevue (98004)
$182,545 median income
- 98118
Seattle (98118)
$113,762 median income
- 98056
Renton (98056)
$113,688 median income
- 98122
Seattle (98122)
$106,886 median income
- 98178 $99,505
Seattle (98178)
$99,505 median income
- 98144 $96,969
Seattle (98144)
$96,969 median income
What this shows By household income, ZIP 98040 ranks #2 of 9 neighboring ZIPs, local affluence varies block to block, not just metro to metro.
| ZIP Code | City | Population | Distance |
|---|---|---|---|
| 98118 | Seattle, WA | 42,731 | 2.4 mi |
| 98039 | Medina, WA | 2,971 | 4.6 mi |
| 98004 | Bellevue, WA | 27,946 | 3.8 mi |
| 98144 | Seattle, WA | 26,881 | 3.1 mi |
| 98178 | Seattle, WA | 24,092 | 4.7 mi |
| 98006 | Bellevue, WA | 36,364 | 3.8 mi |
| 98056 | Renton, WA | 32,489 | 4.2 mi |
| 98122 | Seattle, WA | 31,454 | 4.2 mi |
| 98108 | Seattle, WA | 22,374 | 4.1 mi |
| 98057 | Renton, WA | 10,613 | 6.6 mi |
Nationwide ZIPs with similar ACS profiles
Two Census-derived peer sets for ZIP 98040, both outside WA so the neighborhoods are not geographic containment (Nearby and same-county blocks stay local).
Similar population
Nearest cross-state ZIPs by resident population (22,699 here; floor ≥1,000).
Similar median household income
Nearest cross-state ZIPs by ACS median household income.
More ZIP Codes in King County
Related Areas
Frequently Asked Questions
What county is ZIP code 98040 in?
ZIP code 98040 (Mercer Island) is located in King County, Washington. King County contains multiple ZIP codes, see the full list at /counties/king-wa.
What is the population of ZIP code 98040?
ZIP code 98040 in Mercer Island, WA has a population of 22,699 according to the Census Bureau ACS 2023 estimates.
What is the median household income in ZIP 98040?
The median household income in ZIP 98040 is $219,069, which is 187% above the national average of $76,288.
What is the average home value in ZIP 98040?
The median home value in ZIP 98040 is $2,000,000+, which is 619% above the national average of $278,155.
What is the demographic makeup of ZIP 98040?
The largest racial group in ZIP 98040 is White at 63.6%. Hispanic or Latino residents make up 2.4% of the population.
How many businesses are in ZIP code 98040?
ZIP code 98040 has 830 business establishments employing approximately 7,524 people, according to Census Bureau ZIP Code Business Patterns (ZBP) 2023 data.
What are the main industries in ZIP code 98040?
The top industries by establishment count in ZIP 98040 are: Professional, scientific, and technical services (182), Real estate and rental and leasing (115), Health care and social assistance (108). There are 16 industry sectors represented in total.
How have home values changed in ZIP code 98040?
According to the FHFA House Price Index, home values in ZIP 98040 increased by 32.6% in 2023. Since 2000, home values in this ZIP have appreciated by approximately 190%. This is a developmental index based on repeat sales and appraisal data from Fannie Mae and Freddie Mac.
What is the education level in ZIP code 98040?
In ZIP code 98040, 86.5% of residents aged 25+ have a high school diploma or higher, and 81.4% hold a bachelor's degree or higher. These figures come from the Census Bureau ACS 5-Year Estimates (2023).
What is the average commute time in ZIP 98040?
The mean commute time for workers in ZIP code 98040 is 23.6 minutes according to Census ACS data. The national average is roughly 26 minutes, so commuters here spend less time traveling to work than typical.
What percentage of residents own vs. rent in ZIP 98040?
In ZIP code 98040, approximately 67.0% of occupied housing units are owner-occupied and 33.0% are renter-occupied, based on Census ACS 2023 data.
What is the poverty rate in ZIP code 98040?
The poverty rate in ZIP code 98040 is 3.8% according to Census Bureau ACS 2023 estimates. This measures the percentage of the population living below the federal poverty threshold.
Related
Take this with you
What to do with ZIP 98040's numbers, next.
- See how ZIP 98040 compares to a neighboring ZIP code on the same Census fields Compare this ZIP
- Check where Mercer Island, WA ranks among every U.S. ZIP code on income, education, or homeownership View national rankings
- Save this ZIP to your shortlist to track alongside others you're considering View your shortlist
ZIP Code Tabulation Areas (ZCTAs) are Census Bureau approximations of USPS ZIP codes; figures describe the ZCTA area, not any single address within it.