We take up a longstanding question within the field of European Union (EU) studies: What explains the variation in public support for European integration? There are two dominant explanations: The utilitarian self-interest and the national identity perspectives. The former viewpoint stresses that citizens are more likely to support European integration, if it results in a net benefit to their economy or pocketbook, while the latter perspective argues that identity considerations predominantly influence EU support. Drawing on the concept of double allegiance, we argue that these perspectives should be combined into one single explanatory framework rather than framed as alternatives. Using a multilevel model, we empirically substantiate the claim that interest- and identity-based explanations capture different sides of the same coin, as the more citizens perceive integration to threaten their (economic and social-psychological) security and well-being, the less likely they will support the EU.