Homeowners are discovering that a single climate-risk score can harm their property value and future sales, even when the property has never flooded or burned. These private ratings, based on long-term risk projections, are appearing in listings and turning off potential buyers.

As sites rely on data from firms like First Street, critics argue the models carry a lot of authority but very little accountability, leaving families stuck with lower offers or unsold homes based on forecasts they can’t realistically challenge.