How to read flood risk before buying a home
Start with the official address-area result, then read each flood source separately. High risk means an annual chance above 3.3%, while very low means below 0.1%.
Flood risk can come from rivers, the sea, surface water, reservoirs and groundwater. One low result does not clear the other sources.
England's latest national assessment placed about 6.3 million homes and businesses in areas at risk as at 2025-03-31.
What the bands mean
The four bands describe annual likelihood for the area around a property. High is above 3.3%, medium is 1% to 3.3%, low is 0.1% to 1%, and very low is below 0.1%.
- Band count
- 4
- High min %
- 3.3
- Low min %
- 0.1
- Medium min %
- 1.0
- Very low max %
- 0.1
How this was counted
Postcode district. official annual-likelihood categories for areas around properties.
What to check
Use the address-area service for all available sources. Ask for flood history where the map result or seller's information raises concern, and compare the result with the buildings-insurance terms offered for the property.
- Source count
- 4
- Sources
- rivers and sea, surface water, reservoirs, groundwater where available
How this was counted
Postcode district. sources listed by the address-area checking service.
The national picture
The 6.3 million estimate is national context. The address result and the property's construction carry more weight for a purchase.
- As at
- 2025-03-31
- Homes and businesses million
- 6.3
How this was counted
Postcode district. new National Flood Risk Assessment estimate for England.
Sources and method
- Environment Agency flood and coastal erosion risk management report. 2024 to 2025 report, published 2026. Retrieved 2026-08-03.
- Environment Agency Check the long term flood risk service. live service verified 2026-08-03. Retrieved 2026-08-03.
For an address-specific desk check, Property Diligence’s paid report adds the more detailed property-level information available from public sources.