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Flood Zone A1–A30: What It Means and Whether You Need Flood Insurance

Updated October 2026 · FEMA definitions and NFIP claims for Florida, Illinois, Louisiana, New Jersey, New York, North Carolina and Texas

What Zone A1–A30 means

Zones A1 through A30 appear on Flood Insurance Rate Maps printed before about 1986. They mean the same thing as today’s Zone AE: high risk, studied in detail, with a base flood elevation.

The number once encoded a "flood hazard factor" used in rating. FEMA dropped the numbering in newer maps, so when a county’s map is updated, A1–A30 areas become AE.

Flood claims from Zone A1–A30 buildings

In FEMA’s National Flood Insurance Program claims for Florida, Illinois, Louisiana, New Jersey, New York, North Carolina and Texas, 384,400 claims (21% of claims with a recorded zone) came from buildings rated in Zone A1–A30, with $12.94B paid since 1978. 11,330 of them were for floods in 2015 or later. The typical (median) paid claim was $13K.

Counties with the most Zone A1–A30 claims:

• Orleans Parish, LA — 61,383 claims, $4.38B paid
• Jefferson Parish, LA — 36,003 claims, $819.5M paid
• Galveston County, TX — 19,125 claims, $741.9M paid
• St. Tammany Parish, LA — 15,291 claims, $846.8M paid
• Cape May County, NJ — 14,955 claims, $219.1M paid
• Ocean County, NJ — 13,903 claims, $509.2M paid
• Atlantic County, NJ — 12,350 claims, $322.1M paid
• Pinellas County, FL — 11,508 claims, $99.1M paid

The zone is the one the building was rated in when the claim was paid; maps change over time.

Building rules in Zone A1–A30

Rules are the same as Zone AE: the lowest floor of new or substantially improved buildings must be at or above the BFE.

Flood insurance in Zone A1–A30

Yes, for most buyers. Zone A1–A30 is a Special Flood Hazard Area, so a mortgage from a federally regulated or insured lender — including FHA, VA, USDA, Fannie Mae and Freddie Mac loans — requires flood insurance on the building.

Since FEMA’s Risk Rating 2.0 took effect in 2021–2022, NFIP premiums are priced for each building — elevation, distance to water, rebuilding cost and past claims — rather than by zone alone. The zone still decides whether insurance is mandatory. NFIP covers up to $250,000 for a home and $100,000 for contents, and new policies usually take 30 days to start, so do not wait for a storm forecast. Lenders must also accept qualifying private flood policies.

If you are buying or own a home in Zone A1–A30

• If your paperwork says A1–A30, the map behind it is old. Check the FEMA Map Service Center for the current effective map — the zone or BFE may have changed.
• Ask the seller for the flood disclosure and whether the house has ever had a flood claim — many states require it.
• Check the flood claim history for the ZIP code and county, not only the zone.

Check an address or ZIP code

Our free flood check shows FEMA’s flood zone for an address and how many flood claims were paid nearby. Or search a county or ZIP:

Common questions

Other flood zones

• Zone AE — High risk, with a mapped base flood elevation (BFE).
• Zone A — High risk, mapped by approximate methods — no BFE on the map.
• Zone AH — High risk of shallow ponding, usually 1–3 ft, with a BFE.
• Zone AO — High risk of shallow sheet flow on slopes, usually 1–3 ft deep.
• Zone A99 — High risk, to be protected by a federal flood-control system still being built.
• Zone AR — High risk, behind a decertified levee that is being restored.
• Zone VE — Coastal high risk with storm waves of 3 ft or more; BFE on the map.
• Zone X — Outside the high-risk floodplain. Shaded X is moderate risk; unshaded X is minimal.
• All FEMA flood zones explained

General information, not insurance, legal or real-estate advice. Sources: FEMA flood zone definitions and the NFIP Redacted Claims data set. Confirm the zone for a specific property with FEMA or your local floodplain manager.