One of the principal challenges to increasing energy efficiency investments (EEI) is the lack of statistical data on the actual energy and costs savings achieved with them. Data is still hard to access because it is decentralized and in different formats. Consequently, only a small part of this can be used to produce reliable empirical evidence on the performance of the EEI. EN-TRACK will meet this challenge by enabling an interoperable ecosystem of data and tools supporting building refurbishment decision making, putting it into practice with the financial sector. EN-TRACK builds on an existing infrastructure enabling massive data gathering, making the data comparable and interoperable with other existing databases, analysing this data and offering relevant results to key stakeholders. This will support better (more informed, more transparent and faster) decision-making, contribute to the de-risking of investments in energy efficiency in buildings and facilitate process of closing investment deals. Enabling interoperability with most currently active databases and tools (DEEP, eQuad, EnerInvest, etc.) will lead to an unambiguous data exchange based services ecosystem with low transactional costs. This is a big step towards making energy efficiency investments a mainstream activity of the financial sector. EN-TRACK is a three-year project that will directly involve over 35 financial institutions and 100 key stakeholders with a buildings stock investment capacity of over 442M€, trigger over 23M€ in investments and expects to be achieving annual savings of over 38GWh/yr and 17ktCO2eq/yr by the end of the project. EN-TRACK will become self-sustainable and x10 expansion 5 years post-project is anticipated. The EN-TRACK consortium is a team of 7 from 5 EU countries that includes data and analytical skills, buildings access, leading figures in the energy efficiency financing field, links to the key initiatives (DEEP, EEFIG, etc.), and professional communications skills.