The purpose of this paper is to discuss the impact of the electoral system on turnout, moderated by political knowledge. Following the introduction of the FPTP system to some city councils in the 2014 elections, we used a quasi-experimental design to compare two sets of economically, socially and culturally similar cities, chosen using the Propensity Score Matching method. Data from two waves of a survey with residents, city councillors and local social leaders after the 2014 local elections showed that, despite widespread public debates, knowledge about the electoral system was very low. The results proved that, although the level of political knowledge was higher in the FPTP system than in the PR system, the turnout in the former was lower, even when controlled by political knowledge. However, the joint impact of the electoral system and political knowledge on turnout was mixed, and depended on the method of measuring political knowledge.