Flood Risk by State

Each state's average risk score is the simple mean of the 0–100 composite scores across every one of its counties. A state with avg score 5 is overwhelmingly low-risk; a state with avg score 35+ has the bulk of its land in the elevated-or-worse tier. The composite combines NFIP claims density (40%), disaster frequency (25%), claim severity (20%), and year-over-year trend (15%). See the methodology for the full formula.

Three reasons compound. First, hurricane and tropical-storm exposure drives both disaster declarations and the largest single-event claim totals. Second, NFIP take-up is highest along the coasts because of mandatory-insurance rules in Special Flood Hazard Areas — which means coastal flood losses are more likely to show up in the claims data than inland river flooding. Third, low-lying barrier islands and bayou geography put a much larger share of housing within reach of storm surge.

No state is flood-free. River flooding along the Mississippi, Missouri, Ohio, and Red River systems puts dozens of inland counties in the elevated-or-worse tier, and flash flooding can occur anywhere with a steep drainage basin and a sudden storm. The dataset shows 3,277 counties tracked, and only 95% sit at A — the lowest-risk grade.

NFIP claim payouts are heavily concentrated. A handful of states — typically Louisiana, Texas, Florida, New York, and New Jersey — absorb the majority of dollars in any major hurricane year, while dozens of other states see modest steady losses from river and pluvial flooding. The state breakdown below shows total claim counts, which correlate strongly with payout totals. The highest-payouts ranking drills down to the county level.

State aggregates are recomputed every time the underlying county data is refreshed from the OpenFEMA API. The current refresh covers 99,729 flood-insurance claims and 1,403 disaster declarations, last updated 2026-05-16.