Housing markets in California, New Jersey, Illinois, and Florida are vulnerable to a downturn, with counties near Chicago, New York City, and Inland Empire leading the list, according to a new housing report from ATTOM. These regions accounted for two-thirds of the 50 U.S. counties most susceptible, as affordability gaps, foreclosure filings, and rising unemployment placed increased pressure on local markets and strained affordability.

In total, ATTOM’s analysis ranked 578 counties using four key indicators: affordability, the share of underwater mortgages, foreclosure rates, and unemployment. The analysis identified clusters of high-risk counties in California, Illinois, and New Jersey, with Florida rejoining the list after being less prominent in previous reports. Illinois had six of the riskiest counties, including Cook, Kane, and Will Counties near Chicago, while New Jersey had five, primarily in suburban New York City.

California's at-risk counties were spread throughout the state, from Kern and Merced in the Central Valley to San Bernardino and Riverside in the south.