Several studies have shown that the average citizen is ill-informed about national politics and has even less information about European Union politics. For this reason, partisan voters usually rely on cues from their parties when developing attitudes toward EU issues. This paper argues that, however in need for party cues, partisan voters accept them only if they are familiar enough with the party to know the political values and interests that lead its activity.  The idea is that when a party experiences permanent changes in its structure, the reputational value of its brand decreases, and its cues are less likely to shape voters’ attitudes. Results from multilevel models show that the effectiveness of party cues on EU issues depends on the type of party change, while in an unstable party systems voters are less likely to follow the party line. These findings suggest that partisan voters are not mere passive subjects of the cueing process, but they can actively decide to reject an available cue, even if in need for it.