This contribution explores the possibility of a ‘Hamiltonian moment’ in the European Union (EU) public finances, drawing a parallel with the historical experience of the United States (US) in the late eighteenth and early nineteenth centuries. It examines the different theoretical positions on the existence and scope of the EU’s authority to tax, as well as the legal and political challenges that such an authority would entail. It argues that the EU does have the power to levy taxes for funding its budget, based on Article 311 of the Treaty on the Functioning of the EU (TFEU), but that this power is constrained by the principles stemming from the common constitutional traditions, the respect for national identities, and the need for democratic legitimation. It suggests that a ‘Hamiltonian moment’ in the EU would require a qualitative change in the structure and size of the EU budget, as well as a stronger involvement of the European Parliament and the national parliaments in the decision-making process on the system of own resources.