Journal article: The paper builds upon an original pre- and post-election survey that we conducted before and after the 2015 Canadian election. Directly after Election Day, we asked Canadians for which party they voted, and whether they regret their choice. We find that 39% of them are not perfectly happy with their decision, and 4% even say that they made a bad decision. We show that the propensity to regret can be explained by a mixed-utility theory, whereby voters attempt to maximize a mixture of instrumental and expressive utilities. Our study contributes to the literatures on voting behaviour and political economy, which usually considers that voters are either instrumental or expressive, but not both at the same time.