Do Vote Advice Applications Affect the Party Vote of Young People? Unpacking the Underlying Mechanisms

Voting Advice Applications (VAAs) have become a central campaign feature in many European democracies. While there still is debate about their basic effect on voting―does a VAA ‘advice’ to vote for parties affect people’s actual behavior in the polling booth?―many other questions remain unsolved. It is unclear which exact feature of VAAs or their output exactly explains the potential effect on the vote; for instance, is it the absolute stance overlap between a voter and a given party that matters or rather the relative overlap? Also, questions remain about the durability of VAA effects. And, existing work has looked at positive effect on the vote, but there might be negative effects as well. This study examines these issues among young voters at formative age in Belgium’s (Flanders) 2024 elections. Using a four-wave panel with an embedded controlled VAA survey within-subjects experiment (n = 791) we analyze the effects of exposure to two real-live VAAs. Our results show that VAAs significantly steer young citizens toward congruent parties while actively discouraging a vote for incongruent parties; these effects persist for months after exposure. The congruence, differentiation and surprise of a VAA output all contribute to VAAs’ effects on vote choice.