Flood Risk Tools • How-To Guide

How to Check Your Long-Term Flood Risk

A plain-English guide to the Environment Agency's long-term flood risk checker — how to use it for any address in England, and what the results actually mean for your project.

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Official EA / industry tool
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Step-by-step guide
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What the result means
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Free advice if you need it

What the long-term flood risk checker tells you

The GOV.UK 'Check your long-term flood risk' service is the Environment Agency's free tool for finding out the ongoing flood risk to an area in England — the chance of flooding over years and decades, as opposed to the next few days. It's the first thing we check for any site, and a sensible first step before you buy land or submit an application.

It reports risk from four sources — rivers and the sea, surface water, groundwater (where data exists) and reservoirs — and shows how climate change could increase that risk in future. Each source is graded from very low to high.

Open the long-term flood risk checker →

How to use it — step by step

Four quick steps to get what you need from the tool.

1. Open the checker and enter the postcode

Go to the tool and type in the postcode or place name. It shows risk for the area around an address, not the individual property, so use it as an area indicator.

2. Read each flood source separately

The results are split by source — rivers and sea, surface water, groundwater, reservoirs. A site can be low risk from rivers but medium or high from surface water, so read all four.

3. Check the climate-change view

The service shows how risk could change in future with climate change — important because an FRA has to consider the whole lifetime of a development, not just today.

4. Cross-check with the Flood Map for Planning

The long-term checker is an area indicator; for the flood zone that drives planning, also check the Flood Map for Planning. If either shows Flood Zone 2/3 or medium/high risk, you'll likely need an FRA.

What the result means for your application

If the checker shows anything above low risk — or the Flood Map for Planning puts your site in Flood Zone 2 or 3 — your planning application will usually need a Flood Risk Assessment. The tool won't tell you whether you specifically need one, or design the mitigation; that's what an FRA does. Send us the postcode and we'll confirm, free, whether an FRA is required.

Related: Flood Map for Planning explained  •  When Do I Need an FRA?  •  Flood Risk Report (screening)

Frequently Asked Questions

What do the risk levels in the long-term flood risk checker mean?
Very low means less than a 0.1% chance of flooding in any year, low 0.1–1%, medium 1–3.3%, and high greater than 3.3% (a 1 in 30 chance). The tool reports these separately for rivers and sea, surface water, groundwater and reservoirs.
Is this the same as the Flood Map for Planning?
No. The long-term checker is an area-based indicator of overall risk; the Flood Map for Planning assigns the formal flood zone used in planning decisions. Check both — a site can show low long-term risk yet sit in Flood Zone 2 or 3 for planning purposes.
Does it show the risk to my exact property?
It shows risk for the area around an address rather than the individual building, and it ignores property-level details such as floor levels and local drainage. For a property-specific answer you need a Flood Risk Assessment or a flood risk report.

Not sure what your result means?

Send us your postcode and we'll tell you, free, whether your site needs a Flood Risk Assessment.

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