US Flood-Prone Counties See Net Outflow Amid Rising Insurance Costs and Climate Risk
In 2024, flood-prone counties in the United States experienced a net domestic outflow of 29,027 residents, marking the first time since 2019 that more people have moved out of these areas than into them.
This trend contrasts with low-flood-risk counties, which saw their largest net inflow since 2019 with 35,941 more people moving in than out. The analysis, conducted by Redfin using U.S. Census Bureau migration data and First Street climate-risk scores, defines high-flood-risk counties as those with 23.7% to 99.1% of homes facing high flood risk. Major urban centers such as Miami-Dade County (FL), Harris County (TX), Kings County (NY), and Orleans Parish (LA) drove significant net outflows due to their high share of flood-risk homes and other regional factors.
Miami-Dade led with a net outflow of 67,418 residents, an increase from the previous year, attributed to rising housing costs, insurance premiums, and frequent extreme weather events. Harris County also saw an increase in net outflow, exacerbated by climatic challenges including extreme heat and history of flooding, in addition to economic pressures like rising property taxes and insurance costs. Rising homeowner and flood insurance premiums have substantially impacted these areas, as seen in Miami where premiums have more than tripled over two years. New regulations, such as Florida's post-Surfside condo inspections, have led to higher HOA fees and special assessments, affecting condo market demand.
Historically, flood-prone areas like Houston saw inflows a decade ago but began to experience outflows following Hurricane Harvey in 2017-2019 and economic downturns in oil. The pandemic temporarily reversed this outflow trend, driven by remote workers moving to Sun Belt regions including flood-prone coastal cities. The recent trend reversal is influenced by a combination of high living costs, insurance, politics, and sustained climate concerns.
Some counties, like Pinellas County (FL), experienced their first net outflow in years following significant flood damage from hurricanes, prompting relocations to nearby lower-risk counties such as Pasco County. Pasco saw a substantial net inflow of 20,000 residents, benefiting from lower flood risk and more affordable housing relative to nearby coastal counties.
Survey data indicates that Florida residents cite climate risk as the primary reason for planned moves, whereas Texas residents are more motivated by affordability and space. Flood-prone counties with net inflows tend to have lower median home prices compared to those experiencing net outflows. For example, counties with the highest outflows have median home prices around $437,239, compared to $376,026 in counties with the largest inflows.
Despite domestic outflows, many flood-prone counties continue to see overall population growth from international immigration. Miami-Dade County's population increased due to a significant inflow of immigrants, offsetting domestic losses. However, tighter immigration enforcement may influence future migration dynamics in 2025 and beyond, potentially reducing international population growth in these areas.
The data underscores the complex interplay of climate risk, insurance affordability, housing market dynamics, and regulatory changes shaping migration patterns in flood-prone U.S. counties. Migration trends highlight the growing impact of environmental risk assessments and economic factors on residential choices for both consumers and investors.
The analysis covers 310 high-flood-risk counties from a total of 3,103 U.S. counties with available migration and flood risk data. Net migration figures are derived from U.S. Census Bureau Vintage Population Estimates, reflecting movements from July 2023 to July 2024. Flood risk assessments incorporate current and projected risk over 30 years based on major climate threats like flooding and heat.
Insurance professionals should note the escalation in flood and homeowners insurance premiums in coastal urban centers, regulatory impacts on condominium markets, and shifting demographic patterns driven by environmental risk and cost pressures. These insights are critical for pricing, underwriting, and policy strategy amid evolving climate-related market exposures.
Continued monitoring of migration trends, insurance cost developments, and regulatory responses will be essential to address affordability challenges and resilience planning in high-flood-risk regions. Stakeholders must balance market demands with adaptation measures to mitigate financial and humanitarian impacts from increasing climate risks in vulnerable U.S. counties.