For the first time, a comprehensive map of wildfire risk has been drawn across every address in the continental United States, and it reveals that more than half of all American properties exist within the shadow of fire. The First Street Foundation's analysis — built from over 100 million simulated blazes — arrives at a moment when climate change, decades of fire suppression, and the steady march of development into wild lands have conspired to make the threat both larger and more expensive than any prior generation has faced. Like flood mapping before it, this work asks a quiet but urgent qu
Over half of US properties face wildfire risk in coming decades
More than half of all American homes face wildfire risk
Mark
So this is the first time we've actually had property-level wildfire risk data available to the public?
Mimi
Yes. We've had flood risk maps for decades, but wildfire risk assessment has been fragmented and incomplete until now. First Street built a model using government data on vegetation and weather, then ran simulations of over 100 million wildfires to see which properties they'd threaten.
Luke
How reliable is a model like that? Are we talking about peer review, or is this one organization's estimate?
Mimi
It's peer-reviewed, which matters. But Luke's right to push—modeling future fire behavior is inherently uncertain. The tool gives a rating from one to ten, but that's still a simplification of complex systems.
Mark
And the numbers are really striking. Fifty-six percent of homes facing some risk, 20 million facing moderate risk. Why has it gotten so bad?
Mimi
Three things converging. Climate change has made the West hotter and drier. A century of fire suppression has let vegetation build up to dangerous levels. And people have moved deeper into fire-prone areas, especially in expensive housing markets like California.
Luke
So we're looking at a policy problem as much as a climate problem.
Mimi
Exactly. The suppression piece is something we could theoretically change. The climate trajectory is harder to reverse in the short term.
Mark
What does this mean for someone buying a house right now?
Mimi
They can now type their address into First Street's tool and see their property's rating. That information will also show up on Realtor.com. It's transparency that didn't exist before.
Luke
But does transparency change behavior? If a house is cheap and in a high-risk zone, will people still buy it?
Mimi
That's the open question. The tool exists now. What people do with it is still unfolding.
Mark
And the projections going forward?
Mimi
In thirty years, one in five Americans is expected to live in areas with significant wildfire risk, compared to one in six today. The risk is accelerating.
Le Pouls
- More than 56% of American homes face some wildfire risk over the next 30 years — a scale of exposure that has never before been mapped at the individual property level.
- Wildfire costs have surged nearly tenfold in under a decade, from $8.5 billion to $79.8 billion, signaling that the financial reckoning is already underway.
- Three forces are tightening together: a hotter, drier climate in the West, a century of fire suppression that has loaded landscapes with fuel, and relentless suburban expansion into fire-prone terrain.
- First Street's public search tool and its integration into Realtor.com represent an attempt to put risk knowledge directly into the hands of homeowners and homebuyers before decisions are made.
- Projections warn that within 30 years, one in five Americans will live in areas of significant wildfire risk — meaning the window to act on this information is narrowing.
For the first time, a comprehensive map of wildfire risk has been drawn across every address in the continental United States, and it reveals that more than half of all American properties exist within the shadow of fire. The First Street Foundation's analysis — built from over 100 million simulated blazes — arrives at a moment when climate change, decades of fire suppression, and the steady march of development into wild lands have conspired to make the threat both larger and more expensive than any prior generation has faced. Like flood mapping before it, this work asks a quiet but urgent question: how do we live wisely in a landscape that is changing beneath our feet?
A nonprofit research organization called First Street Foundation has released the most granular wildfire risk assessment ever made available to the American public, assigning every address in the contiguous 48 states a score from one to ten. A score of ten carries a 36 percent or greater chance of a property being caught in a wildfire within thirty years — the length of a typical home mortgage. More than 20 million properties fall into at least the moderate risk category, and one in six Americans currently lives somewhere the foundation classifies as significant risk.
The model behind the ratings is rigorous: First Street drew on government data about dry vegetation and weather patterns, then simulated over 100 million wildfires to determine which properties lay in their path. The work is peer-reviewed. What makes it notable is the gap it fills — flood risk has been mapped this way for decades, shaping insurance markets and development decisions, but wildfire risk assessment has lagged far behind.
The reasons for rising risk are well understood, if difficult to reverse. Climate change has made the Western United States hotter and drier. A century of suppressing fires has allowed dangerous accumulations of dry fuel to build up across the landscape. And Americans have continued moving into the zones where suburbs meet fire-prone wilderness, particularly in California, where housing costs have pushed development into ever more vulnerable terrain. The financial consequences have been severe: wildfire costs jumped from $8.5 billion between 2012 and 2016 to $79.8 billion between 2018 and 2021.
The search tool is now live on First Street's website and will be integrated into Realtor.com, placing risk data in front of people at the moment they consider buying a home. The longer view, however, is sobering — projections indicate that within thirty years, one in five Americans will live in areas of significant wildfire risk, a share that will only grow as the climate continues to warm.
A new analysis has mapped wildfire risk across the continental United States with a precision that didn't exist before, and the picture is stark: more than half of all American homes—56 percent of properties in the contiguous 48 states—face at least some threat from wildfire over the next three decades. The First Street Foundation, a nonprofit research organization, released the findings today along with a public search tool that lets any homeowner or business owner type in an address and see their property's fire risk rating.
The organization assigned every address in the continental US a score from one to ten. A rating of one means close to no risk. A ten means there's a 36 percent or greater chance the property could be caught in a wildfire sometime in the next thirty years—the typical span of a home mortgage. What makes this work significant is not just the scope but the granularity. Until now, there has been no comprehensive property-level wildfire risk data available to the public. Flooding risk has long been mapped this way; the federal government designates areas with a 1 percent annual flood chance as "Special Flood Hazard Areas" for insurance purposes. Wildfire risk assessment has lagged far behind.
The scale of exposure is enormous. More than 20 million properties across the continental US face at least "moderate" wildfire risk, meaning they have up to a 6 percent chance of being in a blaze over a thirty-year period. According to data First Street provided to The Washington Post, one in six Americans now lives in a place with what the foundation classifies as "significant" wildfire risk. To build its model, First Street used government data on available fuels—dry vegetation—and weather patterns, then simulated over 100 million wildfires to determine which properties they might threaten. The work is peer-reviewed.
The risk has grown because of converging forces. Climate change has made the Western US hotter and drier, intensifying fire seasons. A century of fire suppression policy has allowed dangerous levels of dry vegetation to accumulate instead of burning off in smaller, natural blazes. And Americans have continued moving into vulnerable areas where cities and suburbs meet fire-prone ecosystems, particularly in states like California where housing costs have driven development into riskier terrain. The financial toll has exploded: wildfire costs rose from $8.5 billion between 2012 and 2016 to $79.8 billion from 2018 to 2021, according to the National Oceanic and Atmospheric Administration.
The tool is now live on First Street's website, and the organization says the data will also be incorporated into Realtor.com, making it visible to people shopping for homes. But the trajectory is troubling. Both First Street and The Washington Post warn that as climate change continues to warm the planet, the risk will only deepen. Within thirty years, projections suggest that one in five Americans will live in areas facing significant wildfire risk. For now, homeowners can at least see where they stand.
Citations marquantes
Until now, there has been no comprehensive property-level wildfire risk data available to the public, unlike flood risk which has long been mapped for insurance purposes.— First Street Foundation analysis
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