The article examines the legal structure and constitutional consequences of ‘Next Generation EU’ (NGEU)—the innovative recovery fund that the European Union (EU) established to address the socio-economic consequences of the COVID-19 pandemic. The article sheds light on the complex normative constellation that was used to erect NGEU, and explains how this was satisfactorily done within the existing Treaty framework, by resorting to current legal bases. At the same time, however, the article underlines the profound constitutional consequences that NGEU has on the EU's architecture of economic governance. To this end, the article contrasts the strategy chosen to respond to the COVID-19 pandemic to that embraced to tackle the euro-crisis a decade ago, and concludes emphasising how NGEU significantly contributes to the federalisation of the EU, endowing its fiscal union with a fiscal capacity analogous to that of other federal regimes.