High voter turnout gives legitimacy to the political system and strengthens the stability of a country. Since voter turnout matters, it is important to determine which factors boost electoral participation. While there is a vast literature on turnout focusing on institutional, socio-economic, and contextual indicators, there appears to be a shortage of scholarship on the relationship between religion and turnout. In our study, we evaluate the impact of the Islamic religion on electoral participation. Drawing on a large dataset that incorporates all legislative elections worldwide from 1970 to 2010 and controlling for compulsory voting, the electoral system type, the decisiveness of the election, the competitiveness of the election, the size of the country, the regime type and development, we find that Muslim-majority countries have lower turnout rates than majority non-Muslim countries. We also find electoral participation to be lower in countries where Islamic tenets are more strongly entrenched in politics.