Earthquake zones, neighborhood by neighborhood

Every neighborhood, three earthquake zones

Every guide with enough homes to count, sorted by its share of homes in any of the three zones. Sort any column, pick a city, search by name or show only neighborhoods with a zone. Each name opens its guide.

Homes = single-family houses where the records identify them, otherwise lots zoned or coded single-family (marked “lots”). A home counts in a zone when its parcel’s center is inside it. — = not mapped: the state hasn’t evaluated that area for liquefaction or landslide zones (all of Gilroy and 12 of the 446 homes in Skywood, Portola Hills & Skylonda). *Liquefaction and landslide shares in the header leave out homes in unmapped areas.

Where the shares run highest

The neighborhoods with the highest shares of homes in each zone, among guides with at least 100 homes counted. 62 of those neighborhoods have every counted home in a liquefaction zone, so that list shows the largest of them.

How we counted

Neighborhoods

The outlines drawn for our neighborhood guides (approximate; neighboring outlines can overlap). Guides with fewer than 20 counted homes are left out.

Homes

The same homes as our flood and fire zone and lot size counts: single-family houses from city or county assessor records where available, otherwise lots zoned or coded single-family (marked “lots”). Condos and townhomes are not counted.

Zones

The California Geological Survey’s regulatory maps as published in October 2026: Seismic Hazard Zones for liquefaction and earthquake-induced landslides (Seismic Hazards Mapping Act) and Alquist-Priolo Earthquake Fault Zones (Alquist-Priolo Earthquake Fault Zoning Act). A home counts in a zone when its parcel’s center is inside it, so a home whose lot only touches a zone isn’t counted.

Unmapped areas

The state lists areas it hasn’t evaluated for liquefaction or landslide zones. Here that’s all of Gilroy and 12 of the 446 homes in Skywood, Portola Hills & Skylonda, shown as not mapped rather than zero. Fault zones are mapped everywhere here.

Sources by city

Atherton, Belmont, Burlingame, Daly City (unincorporated guides), East Palo Alto, Hillsborough, Menlo Park (unincorporated guides), Millbrae, Portola Valley (unincorporated guides), Redwood City, San Carlos, San Mateo (unincorporated guides) and Woodside: San Mateo County parcel layer (use codes as of June 2020); Campbell: County assessor records (City of Campbell layer); Cupertino: City of Cupertino parcel records; Daly City: City of Daly City parcel and zoning records; Foster City: City of Foster City parcel and zoning records; Gilroy: County assessor records (City of Gilroy layer); Los Altos: City of Los Altos parcel records; Los Altos Hills: County assessor records (fire district layer); Los Gatos and Monte Sereno: County assessor records (Town of Los Gatos layer); Menlo Park: City of Menlo Park parcel and zoning records; Milpitas: City of Milpitas parcel records; Mountain View: City of Mountain View parcel and zoning records; Palo Alto: City of Palo Alto parcel records; Portola Valley: County assessor records (Town of Portola Valley layer); San Bruno: County assessor records (City of San Bruno layer); San Francisco: San Francisco Assessor-Recorder secured roll; San Jose: City of San Jose parcel and zoning records; San Mateo: City of San Mateo parcel layer (county use codes); Santa Clara: City of Santa Clara parcel zoning records; Saratoga: County assessor records (City of Saratoga layer); South San Francisco: City of South San Francisco parcel and zoning records; Sunnyvale: City of Sunnyvale parcel records.

Not included

Morgan Hill (no public parcel layer that identifies single-family homes), areas outside our guide outlines, and guides with too few homes.

Keep going

• Flood & Fire ZonesThe same neighborhoods, with homes in FEMA flood zones and CAL FIRE fire zones.
• Lot Size by NeighborhoodThe same neighborhoods, with median lot size, year built and house size.
• Neighborhoods ComparedEvery neighborhood in a city side by side: lots, flood, fire and earthquake zones in one table.
• Outside Mapped Hazard ZonesThe neighborhoods where no counted home sits in a flood, fire or earthquake zone.
• Earthquake Retrofit GrantsUp to $3,000 from the state to brace and bolt an older house, and which local ZIP codes qualify.
• Insurance LabWhich policies a California home needs, including earthquake coverage.
• Disclosure DecoderWhat each California disclosure means, including the Natural Hazard Disclosure.
• Property Nerds Data LibraryDataset PN-DS-29 has these counts as a CSV, alongside every other dataset we publish.

Counts from the California Geological Survey’s zone maps and public parcel records as published in October 2026 (San Mateo County use codes as of June 2020). Not a substitute for a property-specific report; zone maps change, so check an address with the state’s map.