Free tool

Flood zone lookup by address

Enter a U.S. address to see its FEMA flood zone, whether it’s a high-risk area where lenders require flood insurance, the map panel’s effective date, and the ground elevation.

Free, no sign-up. Uses FEMA’s National Flood Hazard Layer and USGS 3DEP elevation data (via Mapbox).

Not an official determination. This lookup reads FEMA’s public digital flood map at the point we find for the address. It isn’t an official flood zone determination: your lender orders its own, and recent map changes (such as a Letter of Map Amendment or Revision) or preliminary maps may not appear. A building can sit in a different zone than the point on its lot. Confirm on FEMA’s Flood Map Service Center before a purchase or insurance decision.

What the result means

Zones A and V (A, AE, AH, AO, AR, A99, V, VE) are high-risk Special Flood Hazard Areas, inside the 1%-annual-chance (“100-year”) floodplain. Lenders require flood insurance for most mortgages there.
Shaded Zone X (B on older maps) is moderate risk: between the 1% and 0.2%-annual-chance flood limits, or behind a levee.
Zone X (C on older maps) is minimal risk from the rivers and coasts FEMA studied. Local runoff can still flood a house: in the 20 flood-prone counties we analyzed, one in three flood insurance claims came from moderate- and low-risk zones.
Zone D means the flood hazard hasn’t been studied.

For more detail, read Is my house in a flood zone? Why Zone X can still flood.

What a flood zone can’t tell you

Flood maps show where rivers, lakes and the sea are expected to overflow. They don’t show where heavy rain runs downhill and collects, whether the house has flooded before, or how the lot is graded. The ground elevation above gives a first hint: a spot lower than most of the land around it can receive runoff from its neighbors.

Sources

FEMA, National Flood Hazard Layer (flood zones and FIRM panels)
U.S. Geological Survey, 3D Elevation Program (3DEP), via Mapbox terrain tiles