X-tendo will support public authorities to transition to next-generation energy performance certification (EPC) schemes, including improved compliance, reliability, usability and convergence. The key output of the project will be the X-tendo toolbox, a freely available online knowledge hub that will be continued also beyond the project duration. It will contain 10 innovative EPC features ranging from a smartness and a comfort indicator to building logbooks and how to improve EPC databases. For each feature the toolbox will include: (1) solution concepts and good practice examples, (2) description of methodological approaches, (3) calculation tools, and (4) implementation guidelines and recommendations. A selection of twenty-nine test projects in nine different member states will demonstrate the potential of each feature as part of more reliable next-generation EPC schemes across the EU. Intensive stakeholder engagement, experience exchange activities, continuous dissemination and an ambitious exploitation strategy will maximize X-tendo’s impact across the EU. Direct impact on (future) policy making will be achieved by (1) understanding end-users and their needs, (2) engaging with public bodies covering at least 75% of the EU building stock, (3) close collaboration between policy makers and technical, communication and financial experts, (4) outreach to EU-wide initiatives such as the Concerted Action on the EPBD and the European Energy Network, and (5) assessing the viability of policy implementation. Improved and next-generation EPC schemes and the innovative handling and use of EPC-related data will push the market towards better performing buildings and facilitate the interaction between building owners, the construction industry and the finance sector. The combination of the expertise of the project partners and the actions and outputs of the project will steer EPC schemes across Europe to the next-generation requirements.