Does information on parties' position on European integration affect citizen support? Observational research on European Union (EU) politics has long argued that political parties can cue public support for EU policy. Experimental evidence of party cueing effects on citizen support for European integration is mixed, however. We argue that these inconsistent findings are a product of measuring party positions imprecisely. In addition, while research from highly polarized bipartisan contexts shows that both in-party and out-party cues affect citizens' attitudes, it is unclear whether such in- and out-party dynamics hold in less polarized, multi-party contexts. To address these issues, we conduct a survey experiment in which we leverage an actual roll-call vote in the European Parliament to measure party positions on debt mutualization in the European pandemic recovery fund in response to the COVID-19 crisis. Using parties' voting behavior allow us to anchor unambiguous party cues provided in the experiment to a specific real-world situation. The survey experiment is fielded in five EU member-states using nationally representative samples: France, Germany, Italy, the Netherlands, and Spain (N=7500). We find that cues both in- and out-party cues have a statistically significant effect on support for debt mutualization. In-party cues shift preference in the direction congruent with the party position, while out-party cues have the opposite effect.