he advancement of the Internet has not only changed the access to political information but also the structure of information costs for different types of information. We analyze the effects of this change in relative information costs on electoral competition by evaluating the introduction of the voting advice application Smartvote in Swiss cantons. The voting advice application al-lows voters to compare candidates’ policy preferences to their own, thereby reducing costs of information especially on new candidates and small parties which are relatively less well ob-servable through traditional information channels. The Swiss context offers an ideal setting to identify the causal effects of online information as Smartvote was introduced in different can-tons at different points in time which allows us to analyze the effects of online information in a difference-in-difference framework. First results show that the introduction of Smartvote is not associated with higher turnout but with higher vote shares of the smaller parties (and hence low-er vote shares of the bigger parties). This result is consistent with the idea that Smartvote does not lower general information costs enough to lead to a turnout effect, but mainly changes rela-tive information costs, whereby small parties, individual candidates and challengers get an in-formation advantage relative to the situation without Smartvote.