 Ubucco version 0.1 is a comprehensive and openly accessible database of building footprints for 202 million buildings across the 27 European Union countries and Switzerland. The database includes three main attributes, building height, construction year, and type, for respectively 73%, 24%, and 46% of the buildings. It was created by combining 50 open government datasets and open street map with extensive validation analyses to ensure accuracy and consistency. This database provides the foundation for high-resolution urban sustainability studies across scales, continental, comparative, all local, using a single source. This article was authored by Nicola Milo Jettic-Tupont, Felix Wabner, Florian Nactical, and others.