Despite parties being a central part of democracies, voters neither seem to like nor trust political parties. However, little is known about where this distrust stems from, or how parties can redeem voters’ trust in them. Previous research shows that voters tend to prefer parties that use intraparty democracy and evaluate candidates emerging out of democratic procedures better, however, this research assumes that intraparty democracy holds its promise of a democratic procedure. In this paper, we explicitly test how voters evaluate parties and their trust in them depending on whether intraparty democratic follow democratic procedures. We argue that voters should express lower trust in parties and a lower likelihood to vote for them if parties violate principles of competitiveness, participation, and if the decision was reached through a process with a low participation rate. We test our arguments using a conjoint experiment in Germany and explore potential heterogeneities across respondents. Our findings contribute to a deeper understanding of voters’ (dis-)like and (dis-)trust of political parties, as well as to their perception of intraparty democracy.