ZIP Code 94403 — San Mateo city, CA Demographics & Data

ZIP code 94403 covers San Mateo, CA in San Mateo County with a population of about 43,459.

At a glance, the area shows median age of 38.5 (near the U.S. median).

It sits in telephone area code 650; U.S. House district CA-15; the SAN FRANCISCO - OAK - SAN JOSE media market.

San Mateo, CA sits in a university / college context (near college of san mateo (1.6 mi)). Expect stronger interest in student housing, rentals, walkability, transit, and a younger adult age mix versus typical suburban ZIPs.

Median household income in ZIP 94403 is about $179,825 — about 139% above the U.S. median ($75,149).

On socioeconomic markers, US5 shows a poverty rate of 6.4%; unemployment rate near 5.3%; 60.3% of adults with a bachelor’s degree or higher (about 26.6 points above the national share (33.7%)).

Labor and commute patterns include leading industry context around Professional services, Healthcare, and Manufacturing; about 22.4% of workers reporting work-from-home (about 7.2 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 $1,725,900 — about 396% above the U.S. median home value ($348,079).

Housing tenure and rents show median gross rent around $3,083 (about 165% above the U.S. median rent ($1,163)), and owner-occupancy near 54.0% (about 11.4 points below the national owner-occupancy rate (65.4%)).

To comfortably buy a median-priced home in ZIP 94403 in San Mateo, CA, a household would need roughly $475,000 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 $11,087. That is about 164% above the local median household income ($179,825), 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 San Mateo city, CA as Relatively High (composite score 99.2), which is among the highest nationally. The strongest component scores on US5 are flood (98.4) and wildfire (92.0). 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 San Mateo city, CA show little to no average snow and around 19.0 inches of annual precipitation.

IRS migration statistics show a net inflow of about 2,139 for ZIP 94403 (San Mateo city, CA) 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.