Energy poverty is nowadays one of the biggest challenges to be tackled in the European Union, so identifying the number of households in a situation of energy vulnerability and taking the necessary measures to protect vulnerable and energy poor customers is considered to be essential. In this study, a simple methodology for identifying and monitoring energy vulnerable areas based on information available in public databases is presented. This paper brings to light the potential of existing public data for evaluating energy vulnerability, and the nature of these data also enables the evolution of vulnerability levels and the effect of potential measures implemented to be evaluated. The proposed method allows energy vulnerability to be mapped and diagnosed, at census section level, by means of a three-dimensional index that takes into account building features and energy expenses and two socio-economic indicators, giving rise to a vulnerability traffic-light. The method is then illustrated with the evaluation of the energy vulnerability of a region located in northern Spain (Greater Bilbao), where 13% of the census sections or 93,000 inhabitants reside (11% of the total population analysed), have been identified as suffering different levels of energy vulnerability. A geographical pattern has also been clearly recognised. The project leading to these results has received funding from “La Caixa” Foundation under the project code LCF/PR/SR20/52550013. The work has also been supported by the European Union's Interreg Sudoe Programme through the ARCAS project ‘New assessment Methodology for social, sustainable and eco-friendly housing. Climate architecture for the Sudoe's area’, project reference SOE3/P3/E0922. The authors would also like to acknowledge to the Department of Economic Development, Sustainability and Environment of the Basque Government, for making the access to the EPCs database easier.