ZIP Code 98040 — Mercer Island city, WA Demographics & Data

ZIP code 98040 covers Mercer Island, WA in King County with a population of about 25,282.

At a glance, the area shows median age of 45.8 versus a U.S. median of about 38.9.

It sits in telephone area code 206; U.S. House district WA-9; the SEATTLE - TACOMA media market.

Mercer Island, WA aligns with a tech / corporate-campus profile (high remote-work / education / income profile or known campus context). Broadband quality, remote-work share, and nearby employer campuses often matter as much as classic residential stats.

Median household income in ZIP 98040 is about $202,359 — about 169% above the U.S. median ($75,149).

On socioeconomic markers, US5 shows a poverty rate of 4.6%; unemployment rate near 2.5%; 78.8% of adults with a bachelor’s degree or higher (about 45.1 points above the national share (33.7%)).

Labor and commute patterns include leading industry context around Professional services, Healthcare, and Retail trade; about 35.7% of workers reporting work-from-home (about 20.5 points above the U.S. share (15.2%)); a mean commute of about 180.0 minutes (U.S. average near 26.8).

Median home value is about $1,884,200 — about 441% above the U.S. median home value ($348,079).

Housing tenure and rents show median gross rent around $2,332 (about 101% above the U.S. median rent ($1,163)), and owner-occupancy near 66.0% (roughly in line with the national owner-occupancy rate (65.4%)).

To comfortably buy a median-priced home in ZIP 98040 in Mercer Island, WA, a household would need roughly $519,000 in annual income under a 20% down, 30-year loan at 6.8% (illustrative), keeping housing costs near 28% of income. Estimated monthly PITI is about $12,104. That is about 156% above the local median household income ($202,359), so the median earner would likely stretch or need a larger down payment. Rates, taxes, insurance, and HOA fees vary — treat this as a planning estimate, not a lender quote.

FEMA’s National Risk Index rates natural-hazard risk for Mercer Island city, WA as Very High (composite score 99.7), which is among the highest nationally. The strongest component scores on US5 are flood (99.5) and wildfire (79.5). These scores are county-linked NRI values published for planning context — all ZIP codes in the same county share the same composite score on US5. Useful when comparing insurance and disaster exposure across areas, not a substitute for a parcel-level flood or fire determination.

Climate normals for Mercer Island city, WA show little to no average snow and around 36.5 inches of annual precipitation.

IRS migration statistics show a net inflow of about 1,358 for ZIP 98040 (Mercer Island city, WA) on US5’s published series — a signal of people/tax filers moving in relative to those leaving. Inflows often track job growth, housing demand, or lifestyle migration; treat the figure as a directional indicator rather than a precise headcount.