Buying a Home in San Mateo County, CA: Transfer Tax, Rent Control & Coastal/Levee Risk

The City of San Mateo's own conveyance tax is a genuine outlier — and East Palo Alto and Foster City each carry a real, distinct buyer quirk of their own.

San Mateo County's Peninsula geography drives three distinct buyer-relevant patterns: a steeply tiered local transfer tax in San Mateo city (among the state's highest), strong tenant protections in East Palo Alto that predate and exceed the statewide baseline, and real sea-level-rise/levee exposure for bayside communities like Foster City that doesn't show up in a standard hazard disclosure. The Half Moon Bay coastside adds a fourth layer — full California Coastal Zone jurisdiction for the entire city.

What’s the transfer tax in San Mateo County?

The county base is the standard $1.10 per $1,000, but the City of San Mateo adds its own steep tiered conveyance tax that pushes the combined total to $6.10 per $1,000 for most residential sales.

Most cities — including Redwood City, Menlo Park, and Half Moon Bay — charge only the standard rate with no separate city add-on. The City of San Mateo is the exception: following the passage of Measure CC (November 2022), it imposes a tiered conveyance tax on top of the county rate — $5.00 per $1,000 for consideration under $10 million, rising to $15.00 per $1,000 at $10 million or more. Combined with the county rate, that's $6.10 per $1,000 (e.g. $12,200 on a $2M sale), and $16.10 per $1,000 for the rare $10M+ transaction. East Palo Alto's exact local transfer-tax status is disputed in secondary sources — verify directly with escrow before assuming either figure.

Does East Palo Alto have its own rent control ordinance?

Yes — East Palo Alto's Rent Stabilization and Just Cause for Eviction Ordinance, approved by 79% of voters in 2010, is one of the strongest in the county.

It covers most residential rental units regardless of build date, but Costa-Hawkins (1995) still exempts units first occupied after February 1, 1995, single-family homes, and condos from rent caps. For 2026 (July 2025-June 2026), the Annual General Adjustment cap is 2.2% (80% of CPI, statutory max 10%). Eviction requires an enumerated just cause. If buying a rental property in East Palo Alto, confirm build date and current tenancy before assuming market-rate flexibility.

Is Half Moon Bay's entire city inside the Coastal Zone?

Yes — the full City of Half Moon Bay sits within the California Coastal Zone, and while the city issues Coastal Development Permits directly, they remain subject to Coastal Commission oversight and appeal.

A CDP is required for most development consistent with the Local Coastal Program; projects between the sea and the first public road, or within 300 feet of the mean high tide line, can be appealed directly to the Coastal Commission, bypassing the City Council. Budget realistic permitting time for any remodel/addition on the coastside — this is not a rubber-stamp process.

What's the flood/levee risk for Foster City?

Real — Foster City is built on bay fill and sits behind a levee system that FEMA determined in 2014 did not meet minimum flood-protection standards.

Voters passed Measure P, authorizing $90M in bonds funded by a special tax (~$40 per $100,000 of assessed value, ~$560/year on a median-priced home) to fund levee improvements, completed in February 2024 to restore FEMA accreditation and add resilience through 2100. Ask specifically about the special-tax line item and current FEMA flood-zone status before buying in Foster City — this is a real, recurring cost most out-of-area buyers do not expect.

How does the tech job market affect Peninsula home buying here?

San Mateo County's Peninsula cities (Redwood City, San Mateo, Menlo Park, Burlingame) see a buyer pool heavily influenced by nearby tech employment.

RSU vesting schedules and liquidity events (IPOs, acquisitions) can drive noticeable seasonal demand swings, and jumbo-loan financing is the norm rather than the exception for most single-family purchases in these cities — the 2026 conforming loan limit is $1,249,125, the highest FHFA cost tier.

Disclosure landscape

Confirm the City of San Mateo's Measure CC conveyance tax tier before estimating closing costs — it substantially exceeds the standard statewide rate.
Coastal Development Permit requirements apply to essentially all development in Half Moon Bay and the unincorporated coastside — verify with the county or city Planning Department.
Foster City properties carry a Measure P special tax line item tied to levee-bond financing — confirm current status on the property tax bill.
Confirm an East Palo Alto rental property's construction date and current tenancy status before assuming market-rate flexibility.

Frequently asked

How much transfer tax will I pay buying a $2M home in San Mateo city?

$1.10 per $1,000 to the county plus $5.00 per $1,000 to the city (San Mateo's Measure CC sub-$10M tier) — $6.10 per $1,000 combined, or $12,200 on a $2M sale.

Can a landlord in East Palo Alto raise rent however they want after I buy a rental property?

Not on pre-1995 rental units — the city's Rent Stabilization Ordinance caps annual increases (2.2% for July 2025-June 2026) and requires just cause for eviction, though Costa-Hawkins exempts single-family homes and condos from the rent cap regardless of age.

Is Foster City at real flood risk, or is this overstated?

It's real and already being addressed — FEMA flagged the levee as substandard in 2014, and the city completed a $90M levee improvement project (funded via Measure P) in February 2024 to restore accreditation and add resilience to 2100.

Sources

This is educational guidance, not legal advice. Consult a California real estate attorney for legal questions specific to your transaction.