The short answer
The official radon map estimates the likelihood of elevated indoor radon in an area. It does not measure your home. Use UKradon’s map or address report, then arrange a test where recommended.
Go to the official information
Check the map and address report with UKradon. You will leave this website.
Open UKradon map guidance ↗Official address search ↗How to read radon area information
Higher map categories indicate a greater probability that homes exceed the domestic Action Level. A category is a statistical estimate for an area, not a measurement for a particular building.
A postcode is a starting point
Postcodes can cover several buildings and different ground conditions. For a property-specific probability report, use the official address search. No risk score is calculated from your postcode on this website.
Basements need separate consideration
The general map should not be used to dismiss radon risk in a cellar, basement or underground space. Contact with the ground can increase the chance of elevated concentrations irrespective of the mapped category.
What to do after checking
If the official advice recommends testing, arrange a suitable measurement. A neighbour’s result or a low-risk map category cannot prove the level inside your own building.
Sources & further reading
UKHSA: official UK radon maps ↗UKHSA: measuring radon in homes ↗Checked 13 September 2026. General property guidance; use the original source and seek professional advice for your circumstances.