OneGeology is an international collaborative project in the field of geology supported by 113 countries, UNESCO and major global geoscience bodies. It aims to enable online access to dynamic digital geological map of the world for everyone. An EU Joint Research Centre project is using OneGeology geological data as a framework for the production of a Geogenic Radon Map of Europe. The BGS-HPA UK Onegeology Radon Potential dataset provides, within a 1:625,000 scale geological framework, a general indication of how the estimated arithmetic mean ground-floor radon concentration varies within the United Kingdom. The indoor radon data is used with the agreement of the Health Protection Agency (HPA). Mapping of radon-prone areas at the OneGeology 1:625 000 scale can be used to inform European policy makers, politicians and the general public about the general variation of radon potential within the United Kingdom at the European scale. The dataset should not be used at scales larger than 1:250,000 or for regulatory (i.e. Building Control or Radon Affected Area) purposes in the UK.