Theory suggests that majoritarian/plurality elections depress voter participation and that proportional election systems encourage greater voter mobilization and turnout. We examine the effect that cumulative voting (CV) has on turnout in local elections in the U.S. Variation in social/cultural context is largely held constant by our design while election system varies, allowing us to identify the unique effect CV has on turnout. We test if turnout is higher when CV is used in the same context as plurality rules. Consistent with expectations about institutional effects, turnout is about 5 percentage points higher under CV than in similar plurality elections.