This paper examines the relationship between European identity and support for social policy integration within the European Union (EU), utilizing a longitudinal panel dataset to track individual-level attitudes across three distinct time points (2020, 2022, and 2025). Focusing on the evolving attachment to the EU and the salience of European identity, our study investigates how these factors shape preferences regarding the allocation of decision-making authority in social policy. Specifically, the paper explores whether individuals with a stronger European identity are more inclined to favor EU-level governance over national control in the domain of social policy, with a particular emphasis on solidarity. By employing a panel data approach, the analysis captures shifts in individual attitudes, providing a nuanced understanding of the dynamics between EU identity and preferences regarding whether social policies should be decided by national governments, the EU, or jointly. The expected findings suggest that a stronger European identity is positively associated with support for greater EU involvement in social policymaking, particularly in fostering solidarity across member states. This study contributes to the literature on European integration by shedding light on how EU identity influences public opinion on the institutionalization of social policy at the EU level.