It has been suggested that political distrust is associated with lower levels of voter turnout and increased votes for challenger or populist parties. We investigate the relationship between political (dis)trust and electoral behaviour using the 2009 Belgian Election Study. Belgium presents an interesting case because compulsory voting (with an accompanying turnout rate of 90.4 per cent) compels distrusting voters to participate in elections. Nevertheless, distrusting voters are significantly more inclined to cast a blank or invalid vote. Second, distrust is positively associated with a preference for extreme right (Vlaams Belang) and populist (Lijst Dedecker) parties. Third, in party systems where there is no supply of viable challengers (i.e. the French-speaking region of Belgium), the effect of political trust on party preference is limited. We conclude that electoral effects of political distrust are determined by the electoral and party system and the supply of electoral protest.