The Real Cost of Owning in Foster City, CA

Purchase Price: A Real, Disclosed Disagreement Between Sources

Home price trackers disagree sharply on Foster City's current market, and this page states that disagreement rather than picking whichever number sounds cleanest. Zillow's citywide average home value runs near $1.86 million, down roughly 1.0% year-over-year. Redfin's trailing 3-month median sale price runs closer to $1.6 million, up roughly 8.1% year-over-year over the same broad period. A separate June 2026 sold-homes snapshot from another aggregator put that single month's median at $1.43 million across 17 recorded sales -- a thin sample size in a small city, and one that can swing month to month depending on which streets happen to trade. A buyer should treat all three figures as directional, budget from an actual comparable-sales pull for the specific property type and neighborhood in question, and not anchor to any single site's headline number.

That price spread matters more here than in a larger market because Foster City's housing stock is genuinely mixed: high-rise and mid-rise lagoon-view condominiums in developments like Isle Cove, Shell Cove, and the Edgewater Townhouses sit alongside single-family homes in neighborhoods like Sea Cloud and Beach Park, and the two categories can carry very different price points and, as covered on the Waterfront vs. Non-Waterfront page, different lagoon-frontage premiums that this research could not reduce to one clean percentage.

Property Tax: Prop 13 Plus Two Add-On Layers

California's Proposition 13 framework applies here exactly as it does statewide: assessed value resets to purchase price at the time of sale, then rises no more than 2% a year until the next change of ownership, administered by the San Mateo County Assessor's Office. Ownwell's data puts Foster City's average effective property tax rate at roughly 1.22%, slightly below the San Mateo County average of roughly 1.25%-1.26%, with the average Foster City homeowner paying about $9,715 a year against a county average of $11,405 -- a modestly favorable position relative to some other San Mateo County cities, though still a five-figure annual bill at the city's price levels.

Two add-on layers sit on top of that base ad-valorem rate and belong in any honest cost estimate here. First, the Measure P levee special tax: roughly $40 per $100,000 of assessed value annually, repaying the $90 million bond that funded the FEMA-mandated levee rebuild completed in early 2024, for a term the city's voter materials describe as 30 years. Second, San Mateo-Foster City School District parcel taxes -- this research confirmed the district's own parcel-tax program exists (the district maintains a dedicated parcel-tax information page) but did not confirm the current per-parcel dollar amount, which should be pulled from the district or the county tax bill directly rather than assumed from this page.

Insurance: No Flood Mandate Today, But Real California-Wide Cost Pressure

Because Foster City's levee regained FEMA accreditation after the Measure P rebuild, land within city limits sits in flood Zone X, where federal flood insurance is not mandatory for a typical mortgage -- a real, current cost advantage over a market where every parcel sits in a mandatory-purchase flood zone. That does not mean insurance is cheap or optional in a broader sense: statewide reporting places the average California homeowners insurance premium up roughly 84% between the end of 2020 and March 2026, with average deductibles climbing from about $1,813 to $2,553 over the same span, and California's FAIR Plan (the state's insurer of last resort) now covers roughly 5% of California single-family homes, up from 1.5% in December 2020 -- a statewide pressure that is reshaping premiums even in communities, like Foster City, with no wildfire exposure.

This page did not find a confirmed Foster City-specific homeowners insurance premium figure and does not invent one -- see the Coastal Insurance page for the fuller picture, including why some San Mateo County FAIR Plan premiums run high specifically because of the area's high replacement-construction costs rather than fire risk. Get an actual quote from a California-licensed agent before budgeting a number for a specific property.

Sales Tax and Everyday Purchases

Foster City's combined sales tax rate runs 9.375% as of 2026, per Avalara's published rate table -- a real, ongoing cost on furniture, appliances, contractor materials, and any other taxable purchase tied to moving in or renovating. This page did not independently confirm the precise state-versus-county-versus-special-district breakdown behind that combined figure and states the total rather than an unconfirmed itemization.

HOA and Lagoon-Adjacent Maintenance Costs

The lagoon itself -- circulation, floodgates, pumping, and citywide stormwater management -- is a City of Foster City public-infrastructure responsibility funded through general city revenue and the levee special tax, not a homeowner cost. But individual lagoon-front property owners carry their own real maintenance responsibilities: the bulkhead, dock, or shoreline structure adjacent to their own parcel, per guidance covered in more detail on the Dock & Pier Guide page. Condominium and townhome developments along the water -- Isle Cove, Shell Cove, Sea Colony, and similar complexes -- also carry their own HOA dues, which this page did not find a confirmed current range for and recommends pulling from a specific listing's HOA disclosure rather than assuming a citywide average.

What This Page Does Not Know

This page does not have a confirmed single reconciled median home price, a confirmed current San Mateo-Foster City School District parcel-tax dollar amount, a confirmed Foster City-specific homeowners or flood insurance premium, a confirmed precise state-versus-local sales-tax breakdown, or confirmed current HOA dues ranges for the city's various condominium and townhome developments.

Confirm current figures directly with the San Mateo County Assessor's Office, the City of Foster City's Finance Department, San Mateo-Foster City School District, a California-licensed insurance agent, and a local buyer's agent before budgeting a purchase.