Buying a home in an earthquake zone

Key takeaways

• Earthquake risk extends far beyond California. Nearly 75% of the U.S. could experience potentially damaging earthquake shaking, making seismic risk a consideration in parts of the Pacific Northwest, Utah, Alaska and the central United States as well as California.
• Standard homeowners insurance doesn't cover earthquake damage. Buyers in higher-risk areas may need separate earthquake coverage and should understand deductibles, which are often based on a percentage of the home's value rather than a fixed dollar amount.
• A home's construction matters as much as its location. Foundation type, building materials and seismic retrofits can affect earthquake resilience, insurance costs and long-term resale value.

Buying a home in an earthquake zone means evaluating seismic risk, insurance costs and structural condition alongside the standard factors of any home purchase. The U.S. Geological Survey's latest National Seismic Hazard Model found that nearly 75% of the United States could experience potentially damaging earthquake shaking, highlighting how seismic risk extends far beyond California.
Standard homeowners insurance policies generally do not cover earthquake damage, meaning buyers in higher-risk areas face an additional layer of financial planning that many do not initially anticipate.

Similar to buying a home in a wildfire zone, purchasing in an earthquake-prone area introduces risks and costs that buyers in lower-risk markets may not encounter. The risk does not have to be a dealbreaker, but it can affect everything from insurance premiums to retrofit expenses and resale value.

An earthquake zone is an area with an elevated risk of earthquake damage due to nearby fault lines, local geology or a history of seismic activity. Not all earthquake zones carry the same level of risk. A home's exact location, soil conditions and construction can be just as important as whether it sits within a broader seismic hazard area.

Fault lines are fractures in the Earth's crust where tectonic plates move against one another. When stress along a fault is released, it can trigger an earthquake.

Government agencies use geologic data to identify seismic hazard zones where strong ground shaking, surface fault rupture or other earthquake-related hazards are more likely. In California, the Alquist-Priolo Earthquake Fault Zoning Act generally prohibits construction directly on active faults and requires setbacks from mapped fault traces to reduce the risk of surface rupture damage.

Earthquake risk extends far beyond California. The New Madrid Seismic Zone in the central United States, the Wasatch Front in Utah and the Cascadia Subduction Zone off the coasts of Washington and Oregon are among the country's most significant seismic hazards.

A property's distance from a fault tells only part of the story. Ground shaking can cause damage miles from an earthquake's epicenter, and local soil conditions can amplify seismic forces.

Alaska and California experience more earthquakes than any other states, while Washington, Oregon and Utah also face significant seismic risk. According to FEMA, California accounts for the vast majority of the nation's earthquake damage exposure, yet only a small share of homeowners carry earthquake insurance, leaving many households financially vulnerable after a major quake.

Many buyers underestimate earthquake risk outside California, according to Angie Keus, executive vice president of residential earthquake at AGIA, a Brown & Brown company.

"Many buyers underestimate seismic exposure in parts of the Pacific Northwest, as well as portions of Nevada, Utah, Alaska and areas influenced by the New Madrid Seismic Zone," Keus said. "The greatest risk often isn't where people know earthquakes happen. It's where homeowners assume they don't."

Buyers can verify seismic risk for any address using free federal and state mapping tools. Checking these resources before making an offer can help set realistic expectations about insurance costs, retrofit needs and long-term ownership expenses.

The U.S. Geological Survey's National Seismic Hazard Maps provide a national view of earthquake risk, including the likelihood and intensity of ground shaking in a given area. They can help buyers understand a property's overall seismic exposure.

State-level mapping tools offer a more detailed picture. California's Earthquake Hazard Zone Maps identify Earthquake Fault Zones and Seismic Hazard Zones at the parcel level, while Washington and Oregon provide online tools that allow buyers to review local earthquake hazards and other geologic risks.

In California, sellers are also required to provide a Natural Hazard Disclosure Statement, which indicates whether a property is located within a mapped Earthquake Fault Zone or Seismic Hazard Zone.

1. Check federal hazard maps. Search the property's address using U.S. Geological Survey mapping tools to understand its overall earthquake exposure.

2. Review state and local data. State geological surveys can identify nearby fault lines, liquefaction zones and other hazards that may not appear on national maps.

3. Ask for disclosures and property history. Review any Natural Hazard Disclosure reports and ask the seller about prior earthquake damage, repairs or seismic retrofits.

"An earthquake insurance quote can be surprisingly informative, since insurers evaluate many of the same risk characteristics when determining eligibility and pricing," Keus said.

Because seismic maps and hazard assessments are periodically updated as new research emerges, buyers should verify a property's current risk status rather than relying solely on information in a listing description.

Earthquake insurance is a separate policy, or an endorsement added to an existing policy, that covers damage caused by earthquakes. It is not included in a standard homeowners insurance policy, a distinction that often surprises buyers.

Most homeowners insurance policies cover hazards such as fire, wind, theft and certain types of water damage. Earthquake damage is typically excluded.

That means if ground shaking cracks a foundation, damages structural walls or causes a chimney to collapse, repairs generally will not be covered under a standard homeowners policy.

Earthquake insurance typically covers three categories of losses:

• Damage to the home's structure
• Damage to personal belongings
• Additional living expenses if the home becomes uninhabitable during repairs

However, coverage limits, exclusions and deductibles vary by policy, making it important for buyers to review the details before purchasing coverage.

Even with earthquake insurance, some losses may not be covered. Common exclusions can include:

• Flooding, tsunamis or landslides triggered by an earthquake
• Pre-existing structural damage
• Sinkholes
• Vehicle damage, which is generally covered under an auto insurance policy

Property owners should read policy exclusions carefully. The gap between what homeowners assume is covered and what a policy actually pays for can be significant.
Keus said buyers should pay close attention to dwelling coverage limits, coverage for other structures, personal property protection, additional living expense coverage and deductible options.

Earthquake insurance deductibles work differently from standard homeowners insurance. Instead of a fixed-dollar amount, deductibles are typically calculated as a percentage of the home's insured value and commonly range from 5% to 25%.

For example, a homeowner with $400,000 in dwelling coverage and a 15% deductible would be responsible for the first $60,000 of covered damage before insurance benefits begin.

"One of the biggest surprises homeowners encounter is that earthquake deductibles are typically percentage-based rather than fixed-dollar amounts," Keus said. "We recommend focusing on replacement cost rather than simply premium cost."

Several factors affect earthquake insurance premiums, including a home's distance from known fault lines, age, construction type, foundation design, local soil conditions and whether it has been seismically retrofitted.

Keus noted that properties with older foundations, raised foundations, masonry features and other structural vulnerabilities often face higher premiums or more limited coverage options.

For California homebuyers, the California Earthquake Authority, or CEA, is often the most accessible source of earthquake insurance.

The CEA is a publicly managed, privately funded organization that provides residential earthquake coverage through participating insurance companies. It was created after the 1994 Northridge earthquake to help ensure the availability of earthquake insurance in California.

CEA policies generally offer coverage for:

• Damage to the dwelling
• Personal property losses
• Additional living expenses if the home becomes uninhabitable

Deductible options typically range from 5% to 25%.
Buyers in Oregon, Washington and other earthquake-prone states generally rely on private insurers for residential earthquake coverage because they do not have a statewide program similar to the California Earthquake Authority.

A home's structure and foundation are two of the biggest factors in how it will perform during an earthquake. Buyers considering a home in a seismically active area should pay close attention to both.

Wood-frame homes generally perform better during earthquakes than unreinforced masonry structures. Because wood is lighter and more flexible, it can absorb and redistribute seismic forces more effectively. Brick, stone and unreinforced concrete construction tend to be more brittle and more susceptible to cracking or collapse during strong shaking.

Features that can improve earthquake performance include:

• Shear walls that help resist lateral movement
• Cross-bracing for added structural stability
• Steel or reinforced concrete frames designed to flex during shaking
• Lightweight roofing materials
• Foundations that are securely bolted to the structure above

Homes built before modern seismic building codes were adopted may lack some of these protections.

A home's foundation can significantly affect its earthquake resilience.

Homes built on concrete slab foundations generally perform better than older homes with raised foundations and unbraced cripple walls. Cripple walls are the short wood-framed walls between the foundation and the first floor. During an earthquake, these walls can fail, causing part of the structure to shift or collapse.

Buyers should ask whether a home is bolted to its foundation and whether any cripple walls have been braced.

"Many earthquake-related vulnerabilities are subtle and may not be obvious at first glance," said Keus. "Buyers should pay close attention to signs of prior movement or structural stress, including cracks in foundations or chimneys, sloping floors, and doors or windows that no longer align properly."

Keus said a general home inspection is valuable, but buyers in higher-risk areas may also want to consult a structural engineer or seismic specialist.

Seismic retrofitting involves upgrading an existing structure to better withstand earthquake shaking. Common improvements include foundation bolting, cripple-wall bracing, chimney reinforcement and securing water heaters to reduce the risk of gas-line failures.

According to the California Residential Mitigation Program, a standard brace-and-bolt retrofit typically costs between $3,000 and $7,000 when completed by a licensed contractor, though more extensive projects can cost significantly more.

Retrofitting can improve both a home's resilience and its insurability.

"Earthquake retrofits generally improve a home's resilience and can make a property more attractive to buyers," Keus said. "Some carriers recognize retrofitting efforts and may offer more favorable underwriting treatment or premium credits, depending on the type and extent of improvements."

Earthquake risk can affect buyer demand, insurance costs and resale value, but the impact varies by market.

Homes located near active faults or in high-risk seismic areas may attract fewer buyers, particularly if insurance is expensive or major retrofits are needed. In some cases, that can put downward pressure on prices.

In high-demand markets such as Los Angeles, San Francisco and Seattle, however, location often outweighs seismic concerns. Many buyers accept earthquake risk as a trade-off for access to jobs, amenities and the lifestyle those markets offer.

Properties with documented seismic upgrades — such as foundation bolting, braced cripple walls or other retrofits — are often easier to insure and may be more attractive to future buyers.

Seismic exposure is one of many location-related factors that can influence a home's long-term value, alongside school quality, commute times and neighborhood amenities.

Before submitting an offer, take these steps:

1. Verify earthquake risk. Check the property's seismic exposure using U.S. Geological Survey hazard maps and state geological survey tools.
2. Review hazard disclosures. Ask for any Natural Hazard Disclosure reports and inquire about known earthquake-related risks.
3. Get insurance quotes. Obtain earthquake insurance estimates to understand potential premiums and deductibles before closing.
4. Evaluate the structure. Confirm whether the home has been retrofitted, bolted to its foundation or otherwise upgraded to meet modern seismic standards.
5. Consider a structural engineer. A specialist can identify vulnerabilities that may not surface during a standard home inspection.
6. Estimate retrofit costs. If upgrades are needed, obtain contractor estimates and factor those costs into your offer.
7. Calculate the total cost of ownership. Include insurance premiums, potential retrofit expenses and ongoing maintenance alongside the purchase price.

Usually not. Most mortgage lenders require homeowners insurance but do not require earthquake insurance, even in areas with elevated seismic risk. Unlike flood insurance in federally designated flood zones, there is no federal requirement for earthquake coverage. Buyers who forgo earthquake insurance, however, remain responsible for any earthquake-related repair costs.

No. Like any insurance policy, coverage from the authority includes limitations and exclusions. Coverage generally applies to damage to the home, personal property and additional living expenses, but certain losses may not be covered or may be subject to limits. Buyers should review policy details carefully and compare authority coverage with private-market options to determine which best fits their needs.

Yes. If inspections or engineering reports identify seismic upgrades that are needed, buyers can ask the seller to complete the work before closing, lower the purchase price or provide a credit toward the repairs. Seismic retrofit costs are often negotiated during the inspection period, especially in earthquake-prone markets.

Soil liquefaction occurs when water-saturated soil loses strength during an earthquake and temporarily behaves like a liquid. This can cause foundations to settle unevenly, tilt or crack, even if the home's structure is otherwise sound.

Properties built on fill dirt, sandy soils or reclaimed land are generally more vulnerable. Buyers can research liquefaction hazards using state and federal mapping tools and, if necessary, hire a geotechnical engineer for a site-specific assessment.

In some areas, yes. California's Earthquake Brace + Bolt program helps eligible homeowners offset the cost of foundation bolting and cripple-wall bracing. Local governments and hazard-mitigation programs may also offer grants, rebates or low-cost financing for seismic upgrades.

Not always, but homes built under modern seismic building codes generally perform better than those built before current standards were adopted. Construction quality, foundation type, maintenance and whether a home has been professionally retrofitted can be just as important as its age.

Not necessarily. Many of the country's most desirable housing markets are located in earthquake-prone areas. The key is understanding the risks before you buy, including insurance costs, structural condition and any retrofit needs. For many buyers, earthquake risk is simply another factor to weigh alongside price, schools, commute times and neighborhood amenities.

Related content:

• Buying a home in 10 steps
• Buying a home in a fire zone