As a consequence of the euro crisis, economic and fiscal policy-making competencies have been transferred to the EU-level. At the same time, national parliaments have seen their capacity to influence the policies to combat the crisis curbed. This contribution explores the reaction of national parliaments to the crisis and demonstrates stark variation in their capacity and willingness to adapt institutionally to the crisis. The analysis underlines the causal relevance of existing EU- and budget-related competencies that national parliaments possess to account for their willingness and ability to adapt institutionally. The euro crisis thus cements and perpetuates already existing differences between strong and weak parliaments.