Covid-19 posed a severe stress test to crisis management in the European Union (EU). Neither the member states nor the EU institutions managed to coordinate a swift and effective crisis response. This thesis argues that the core weakness in the EU’s Covid-19 response lay in the uncertainty over the division of competencies. In other words, it was uncertain how the responsibilities between the member states and the EU institutions would be divided. As this is a classical federal problem, this thesis makes a unique contribution by comparing the EU’s Covid-19 response with two federations, Germany and the U.S. In doing so, this thesis shows that a ‘federal lens’ can inform EU crisis management. For a long time, federalism was stigmatized and downplayed, however, this work highlights its promising value as an analytical as well as a prescriptive tool. The findings reveal that the EU should move towards the cooperative structure of the German system while keeping a level of flexibility.