Free tool · Powered by the Flood risk and ground risk APIs
Flood and ground risk checker
Enter a postcode to screen it against public flood maps and ground hazard datasets: rivers and the sea, surface water, reservoirs, past flooding, coal mining, recorded landslides and geology.
Checks the postcode's central point and a 250 metre radius around it. Some sources can take a few seconds to respond.
What this checker looks at
The checker takes the central point of the postcode and screens it against official public datasets. Flood zones, flood likelihood and surface water maps are checked at that point. Flood defences and recorded landslides are searched within 250 metres.
Flooding
In England, results come from Environment Agency datasets: Flood Zones 2 and 3, the risk of flooding from rivers and the sea, the risk of flooding from surface water, reservoir flood extents, national coastal erosion risk mapping, recorded flood outlines and flood defence assets. In Wales, results come from Natural Resources Wales flood risk maps for rivers, the sea and surface water.
Ground
Ground results use Mining Remediation Authority coal mining layers, the British Geological Survey National Landslide Database and BGS 1:50,000 geology. Geology is shown as context, such as made ground or mapped mass movement deposits. It is not a ground stability rating. The ground risk API docs list every layer.
What the results do and do not tell you
This is a screening of public datasets at postcode level. A postcode can cover several streets, so a single home may sit inside or outside a mapped area even when the postcode point does not. Treat a match as a reason to look closer, and an empty result as "nothing found in these datasets", not as proof that a property is safe.
It is not a formal flood risk assessment and it does not replace the environmental, drainage or mining searches your conveyancer orders. For a purchase, mortgage or insurance decision, rely on those searches and on advice from a qualified professional.
Using the data in your own product
The same checks are available as two endpoints. The flood risk API returns each flood source with its risk level and details, and the ground risk API returns coal mining, landslide and geology results. Both accept a postcode or coordinates and a search radius.
Frequently asked questions
Is this an official flood risk assessment?
No. It screens official public datasets at the postcode point. It is useful for spotting where to look closer, but it is not a formal flood risk assessment and it does not replace the environmental and mining searches ordered during conveyancing.
What does "None found" mean?
It means the datasets we checked have no mapped risk at that point or within the search radius. It does not prove a property has never flooded or has no ground problems, as maps have limits and a postcode can cover a wide area.
Which parts of the UK are covered?
Flood screening covers England, using Environment Agency data, and Wales, using Natural Resources Wales data. Several flood checks, such as reservoirs and recorded past flooding, are England only. Ground screening covers Great Britain. Northern Ireland is not covered.
Why does it say a source was incomplete?
The checker queries several public services live. If one of them does not respond, we show the result as incomplete rather than reporting no risk. Try again a little later.
Will a high result affect my mortgage or insurance?
Lenders and insurers use their own data and assessments, so this checker cannot tell you how they will treat a property. Use it as a starting point for questions to your conveyancer, surveyor or insurer.
Free lookups are limited per visitor to keep the service fast for everyone. For bulk or automated use, use the API.