International actors promoted the transfer of regulatory authority and financial resources from national governments to the European Union in the context of establishing the prerequisites for financial stability in Europe through banking union. It was supplied, however, by a political process that kept significant resources in resolution and deposit insurance largely in national hands. This paper examines the politics behind those decisions, and how the hybrid of European and national competences affects bank regulation and financial stability in the EU. It concludes that the tension between strong EU supervisory powers and weak capacity to deal with insolvent institutions will persist.