H
igh‑risk flood counties in the U.S. experienced a net loss of 29,027 residents last year, the first decline since 2019. Low‑risk counties, by contrast, added 35,941 people, the largest gain in recent history. The data come from a Redfin analysis of U.S. Census domestic migration (excluding immigration) and First Street flood‑risk scores. A county is “high‑risk” if it ranks in the top 10 % of homes facing major, severe, or extreme flood risk (23.7 %–99.1 % of homes).
### Key Outflow Drivers
| County | Net outflow | Flood‑risk share |
|--------|-------------|------------------|
| Miami‑Dade, FL | –67,418 | 36.3 % |
| Harris, TX | –31,165 | 31.3 % |
| Kings, NY | –28,158 | 25.0 % |
| Hudson, NJ | –12,735 | 27.2 % |
| Jefferson Parish, LA | –5,126 | 98.8 % |
| Orleans Parish, LA | –4,950 | 99.1 % |
| Pinellas, FL | –3,973 | 35.8 % |
| Norfolk City, VA | –2,550 | 32.4 % |
| Cameron, TX | –1,946 | 28.0 % |
| Fairbanks North Star, AK | –1,849 | 28.8 % |
Miami‑Dade’s outflow widened from 50,637 in 2023 to 67,418 in 2024, the sharpest increase among high‑risk counties. Harris County’s net outflow grew from 22,035 to 31,165, the second‑largest acceleration. Kings County, Hudson County, and the Louisiana parishes also posted significant losses.
### Why People Leave
- **Climate risk**: Rising flood frequency, higher insurance premiums, and extreme weather events (e.g., Hurricane Helene’s $93 million damage in Pinellas County) push residents out.
- **Cost of living**: Home prices, mortgage rates, and property taxes have surged, especially in Texas and Florida. In Houston, the average home price rose sharply during the pandemic boom and remains high.
- **Insurance and HOA costs**: Flood insurance premiums in Miami climbed from <$2,000 to $6,700 annually, while flood coverage rose from $400 to $1,250. Condo owners face new structural‑inspection mandates and higher HOA fees after the Surfside collapse.
- **Political and lifestyle preferences**: Some former pandemic migrants find the heat, politics, and lifestyle in Houston and Miami less appealing than expected.
A Redfin‑commissioned Ipsos survey (May 2025) of ~1,200 U.S. homeowners and renters who plan to move in the next year found that “concern for natural disasters or climate risks” was the top reason for Floridians, but only the seventh most common reason for Texans.
### Migration Patterns
- **Domestic net outflows**: 132 of 310 high‑risk counties saw more people leave than arrive. The remaining 178 counties had net inflows, largely driven by immigration.
- **Immigration’s role**: Miami‑Dade’s population grew 2.3 % in 2024, largely due to 123,835 net international migrants—the highest for any U.S. county. Six of the ten counties with the largest domestic outflows still grew overall because of foreign‑born residents.
- **Suburban pull**: Montgomery County, TX (low‑risk) recorded a net inflow of 23,919, the largest in the country, as people move to safer suburbs.
### Net Inflows in High‑Risk Counties
| County | 2024 net inflow | 2023 net inflow | Flood‑risk share |
|--------|-----------------|-----------------|------------------|
| St. Johns, FL | 11,661 | 11,878 | 27.0 % |
| Fort Bend, TX | 10,467 | 15,593 | 37.3 % |
| Volusia, FL | 9,724 | 12,009 | 29.1 % |
| Brunswick, NC | 8,011 | 7,503 | 26.4 % |
| Brazoria, TX | 7,382 | 8,298 | 53.7 % |
| Sussex, DE | 6,507 | 7,045 | 25.0 % |
| Charlotte, FL | 5,981 | 4,949 | 78.9 % |
| Citrus, FL | 5,163 | 5,962 | 25.6 % |
| Flagler, FL | 5,077 | 5,111 | 33.4 % |
| Bay, FL | 5,074 | 4,755 | 28.5 % |
These inflow counties tend to be more affordable: the median home sale price in the ten counties with the largest outflows was $437,239, compared with $376,026 in the ten with the largest inflows.
### Recent Shifts
- **Pinellas County**: The first county in the table to record a net outflow in years, driven by Hurricane Helene’s flooding. Many residents relocated to Pasco County or out of state.
- **Harris County**: Outflow accelerated to 31,165 in 2024. Residents cite extreme heat, high taxes, and rising insurance costs. Some are moving to suburbs like Montgomery County.
- **Immigration slowdown**: Redfin agents report a sharp decline in international buyers, especially from Latin America and Canada, due to stricter U.S. immigration enforcement.
### Methodology Overview
- **Flood risk**: First Street’s six‑tier climate‑risk categories (minimal to extreme). High risk = major, severe, or extreme. Counties in the top 10 % of high‑risk homes are classified as high‑risk.
- **Migration**: U.S. Census Vintage Population Estimates (July 2023–July 2024). Net domestic migration = in‑moves minus out‑moves.
- **Scope**: 3,103 counties with both migration and flood‑risk data. Total net outflow for high‑risk counties: –184,249; total net inflow: 155,222; net national outflow: –29,027.
The analysis highlights a growing trend of residents leaving flood‑prone areas for affordability, climate, and lifestyle reasons, even as immigration continues to offset population losses in many high‑risk counties. The next year may see further shifts as federal immigration policy tightens and climate impacts intensify.
