Check Radon Risk by Postcode
Find out if your home is in a high-risk area based on BGS geological data
What is radon?
Radon is a naturally occurring radioactive gas produced by the decay of uranium in rocks and soil. It seeps into buildings through floors and walls and, when it accumulates indoors, is the second leading cause of lung cancer in the UK — responsible for around 1,100 deaths each year. Radon is invisible and odourless; the only way to know your home's level is to test.
Learn how to test for radon and what to do if levels are high →
Highest Risk Counties in England
Counties ranked by average radon risk class across all postcode districts.
How it works
- 1
Enter your postcode
Type any UK postcode or district code (e.g. EX1, SW11)
- 2
See your risk level
Instant result based on BGS data for your postcode district
- 3
Take action if needed
Order a test kit and get expert guidance on reducing radon levels
Get a Radon Test for your area
The only way to know your home's radon level is to test. Radon levels in your area are classified as area-specific — a test takes 3 months and costs around £29.
From ~£29 · 3-month detector Airthings Corentium Home
~£99 · Digital · Ongoing monitoring
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Data: BGS Radon Indicative Atlas v3 (OGL v3). Postcode data: ONS NSPL Feb 2026 (OGL v3).