This data article refers to the paper "What is a Nearly zero energy building? Overview, implementation and comparison of definitions" (D׳Agostino and Mazzarella, 2019). Data linked with this article allow an overview of the European status in relation to energy consumption and energy savings in buildings. Further data are available in relation to Nearly zero energy buildings (NZEBs). Data relate to primary and final energy consumption, detailing electricity, gas, oil, coal, heat, and wood consumption from 1994 to 2014 in different countries. Data also relate to the stock of constructions of total, single-family, and multi-family dwellings in Europe. Energy consumption per different energy carriers is also given for the residential sector in European and non-European countries. Energy consumption and savings trends can be visualized. In relation to NZEBs, selected retrofit case studies in Europe are presented. Data include energy consumption, saving percentages, costs, payback period, implemented efficiency measures and renewables. Further data is available about building geometry, costs, envelope, lighting, appliances and systems.