Coastal flooding risk by county
Sea water pushed onto land by storm surge, very high tides or strong onshore winds. Low-lying neighborhoods near bays and inlets see it most.
Highest expected losses
| # | County | Rating | A year |
|---|---|---|---|
| 1 | Charleston County, SC | $36M | |
| 2 | Bergen County, NJ | $34M | |
| 3 | Cape May County, NJ | $31M | |
| 4 | Suffolk County, NY | $25M | |
| 5 | Pinellas County, FL | $25M | |
| 6 | Nassau County, NY | $24M | |
| 7 | Grays Harbor County, WA | $24M | |
| 8 | Miami-Dade County, FL | $23M | |
| 9 | Monroe County, FL | $21M | |
| 10 | Marin County, CA | $20M | |
| 11 | Essex County, MA | $19M | |
| 12 | Ocean County, NJ | $19M | |
| 13 | Manatee County, FL | $17M | |
| 14 | Plymouth County, MA | $14M | |
| 15 | Salem County, NJ | $14M |
Big counties lead this list partly because they have more people and buildings at risk.
Highest per resident
| # | County (100,000+ people) | Per person a year |
|---|---|---|
| 1 | Charleston County, SC | $87 |
| 2 | Terrebonne Parish, LA | $83 |
| 3 | Marin County, CA | $75 |
| 4 | Sussex County, DE | $60 |
| 5 | Skagit County, WA | $54 |
| 6 | Barnstable County, MA | $54 |
| 7 | Beaufort County, SC | $53 |
| 8 | Atlantic County, NJ | $51 |
| 9 | Chatham County, GA | $45 |
| 10 | Manatee County, FL | $42 |
Expected yearly loss divided by population. A fairer way to compare places of different size.
Lowest risk among large counties
| # | County (250,000+ people) | Rating | Per person a year |
|---|---|---|---|
| 1 | Montgomery County, MD | under $1 | |
| 2 | Fort Bend County, TX | under $1 | |
| 3 | Clackamas County, OR | under $1 | |
| 4 | Howard County, MD | under $1 | |
| 5 | Passaic County, NJ | under $1 | |
| 6 | Marion County, FL | under $1 | |
| 7 | Leon County, FL | under $1 | |
| 8 | Cuyahoga County, OH | under $1 | |
| 9 | Cook County, IL | under $1 | |
| 10 | Milwaukee County, WI | under $1 |
How ratings are spread
The lists above show only the top counties, so they are all rated high. Across all 436 rated counties, most are Low or Very Low:
How to prepare
- Learn your evacuation zone; it is set by surge risk, not by distance from the beach.
- Ask about flood insurance even outside a mapped high-risk zone.
- Note how often nearby streets flood at high tide.
States where it is most often the top hazard
Read more
Storm surge explained: the deadliest part of a hurricane
What storm surge is, why it is so dangerous, how high it can get, and how to know if your home is in a surge evacuation zone.
The 30-day flood insurance waiting period: when to buy
Why most federal flood policies take 30 days to start, the few exceptions, and why buying when a storm is coming is usually too late.
Moving to a new county? A disaster risk checklist
Eight things to check about natural hazards before you buy or rent in a new place, from flood zones to insurance quotes.
Common questions
Which US county has the highest coastal flooding risk?
Charleston County, SC has the highest expected yearly coastal flooding losses in FEMA's National Risk Index, about $35.6 million a year. Bergen County, NJ is second at $34.3 million.
How many counties face coastal flooding risk?
FEMA rates coastal flooding in 436 of 3,144 counties in the 50 states and DC. 29 are rated Very High and 60 Relatively High.
Is coastal flooding covered by home insurance?
No. Flood damage needs a separate flood policy, from the National Flood Insurance Program or a private insurer.
Other hazards
Source: FEMA National Risk Index (December 2025). Expected annual loss is FEMA's long-run estimate of yearly damage to buildings, people and farm output, in dollars.