AbstractIssue ownership is an important determinant of the vote, and it is electorally beneficial for parties to build a strong reputation on their core issues. Even though issue ownership has already been studied extensively in the party literature, we know less about how citizens form ownership perceptions. We contribute to this literature by means of two studies on the connection between party behaviour and perceptions of issue ownership, with an empirical focus on issue competence reputations of parties. In Study 1, we combine party‐level information about issue attention, positions and performance with data on competence perceptions from a wide range of national election studies. Study 2 is a pre‐registered conjoint experiment designed to examine the causal link between party behaviour and perceived competence. Our results point to significant effects for all three hypothesised sources of competence reputations. Moving beyond previous work that has argued that competence reputations are mostly stable over time, after accounting for the variation due to parties' popularity, our results show that they fluctuate in the short term and that parties have some level of control over how they are perceived.