San Mateo, CA population, income and ZIP codes

San Mateo city is a mid-size city in California, with 103,555 residents counted in the Census American Community Survey 2019-2023 ACS 5-year estimates, which places it #72 of 1,618 ranked by population — larger than 95% of them. The median age here is 38 years against 39.1 nationally, a slightly younger profile than the country as a whole. At this size the Census also publishes one-year estimates; the five-year values used here are steadier and let you compare against smaller neighbours on the same basis.

Households in San Mateo city earn a median of $152,669 a year, 94.4% above the national figure of $78,538 and 68% above the $91,111 median for the 1,050 California cities we cover. Household income here is measured before tax and pooled across everyone at the address, which is why it reads higher than typical individual earnings in the same area. Poverty reaches 7.9% of residents here, below the 12.4% national rate.

The typical owner-occupied home in San Mateo city is valued at $1,563,200, 415.2% above the national figure and 165% above the $589,600 peer median, while median gross rent runs $3,079 a month, 119% above the national figure, or roughly $36,948 across a full year. A household on the local median income would put about 24.2% of gross pay toward that rent against the federal 30% cost-burden threshold, so renting here is within the standard affordability guideline. The home-price-to-income ratio works out to 10.2×, against roughly 3.9× nationally, so buying is out of reach on local earnings alone and the ownership market leans on outside income, equity or dual high earners. 50.8% of occupied homes are owner-occupied versus 65% nationally, so the market leans more heavily on renters. The rent line includes utilities paid by the tenant, a definition worth remembering when comparing it against a landlord's quoted rate.

Home values sit at 10.2× median household income, far past the 3.9× national mark, so ownership costs here are set by something other than local wages — second homes, retirees with equity, or commuters earning elsewhere.

No figure on this page is estimated by us; each one comes straight from the published ACS tables for this area. Small-area estimates still carry wider margins of error than state or national figures, so check the linked ACS tables before relying on them for lending, appraisal or legal work.