Zone A is the high-risk flood zone that slows a deal down. The risk is the same as AE, but the map leaves out the one number a builder needs. Here is what that means, what to ask before you buy, and where it shows up in Florida.
Check any lot's flood zone in secondsFlood zone, wetlands, soil and owner, in one search.See how it worksFlood zone A meaning, in short: Zone A is part of FEMA's special flood hazard area, land with a 1% chance of flooding in any given year (the 100-year floodplain). Unlike Zone AE, the flood map does not show a base flood elevation, the height the 1% annual chance flood is expected to reach. Without that number, nobody can say how high the house has to sit until it is established for the lot.
FEMA defines the special flood hazard area as "the area that will be inundated by the flood event having a 1-percent chance of being equaled or exceeded in any given year", and Zone A is one of its labels. FEMA's definition of the base flood elevation lists the zones where the flood map shows one, such as AE, AH and VE. Plain Zone A is not on that list.
That matters because a new home's lowest floor has to be at or above the flood elevation the building department requires, which starts from the BFE. On an AE lot you read that number off the map. On a Zone A lot it often has to be found first: from data the county already has, or from an engineer or surveyor working it out for the lot. Until it is, nobody can price the pad.
Zone A is high risk, so the same rule applies as in AE: with a federally backed mortgage, flood insurance is required as a condition of the loan. According to FloodSmart, homes in high-risk areas have a 1 in 4 chance of flooding at least once over a 30-year mortgage.
FloodSmart also notes that owners in Zone A "may need elevation certificates" to show the property meets local flood safety requirements. An elevation certificate does not set the premium, but it can identify discounts, and under Risk Rating 2.0 the zone is no longer the only factor in the price.
Less common than AE in most markets we measure, but a big share in a few. Share of our sampled points in Zone A:
| Market | Zone A |
|---|---|
| Daytona Park Estates | 46% |
| Palm Coast | 21% |
| Bunnell | 18% |
| Poinciana | 15% |
| Silver Springs Shores | 13% |
| Deltona | 12% |
| Weeki Wachee | 9% |
| Lakewood Park | 8% |
| Sebastian | 7% |
Our numbers: for each market we sampled 121 evenly spaced points on 15 September 2026 against FEMA's National Flood Hazard Layer, the same layer the app reads. Where FEMA returned no zone for a point, the share is of the points it did answer for.
Silver Springs Shores is the unusual one: 87% Zone X and 13% Zone A, with no Zone AE at all, so every hazard point we sampled there came without a published flood elevation. See the Silver Springs Shores breakdown.
| Zone | Risk | Base flood elevation on the map | Flood insurance with a federally backed mortgage |
|---|---|---|---|
| X (unshaded) | Minimal | No | Not required, lender may still ask |
| X (shaded) | Moderate | No | Not required, lender may still ask |
| A | High (1% a year) | No | Required |
| AE | High (1% a year) | Yes | Required |
| VE | High, coastal, with waves | Yes | Required |
Read next: flood zone AE, the high-risk zone with a published flood elevation, and flood zone X, the moderate and minimal risk zones.
Sources: FEMA flood zones glossary, FEMA Zone AE, FEMA base flood elevation, FloodSmart: what is my flood zone, FloodSmart: what is my flood risk, FEMA Risk Rating 2.0, FloodSmart: elevation certificates, Florida Division of Emergency Management. Checked 26 October 2026. This is general information, not insurance or legal advice.
Zone A is part of FEMA's special flood hazard area, land with a 1% chance of flooding in any given year, where the flood map does not show a base flood elevation.
The flood risk category is the same: both are high-risk zones with a 1% annual chance of flooding. Zone A is harder to plan around because the map gives no base flood elevation, so the height to build to often has to be established for the lot first.
If the property has a federally backed mortgage, yes. Flood insurance is required as a condition of the loan in high-risk zones, which include Zone A.
Usually, yes, but the building department will need a flood elevation to build to. Ask the county's floodplain manager whether one is already available for the lot before you buy.
Start with the county or city floodplain manager, who may already have flood elevation data for the area. If not, it is typically established for the lot by an engineer or surveyor.
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