This article analyses the impact of populist right-wing parties (PRWPs) on welfare state reforms in Western Europe in the light of the trade-off that they face between office and votes. On the one hand, PRWPs appeal to traditionally left-leaning blue-collar “insiders” supportive of social insurance schemes. On the other hand, they have only been able to take part in government as junior coalition partners with liberal or conservative parties who are more likely to retrench these very same welfare programs. In this context, the article argues that these parties have to choose between betraying their electorate (and losing votes), and betraying their coalition partners (and losing office). When they choose office, it enables welfare state retrenchment by allowing their coalition partners to curtail left-wing opposition, but entails high electoral costs for PRWPs. When they choose votes, it generates deadlock and potentially jeopardises their participation in government. The paper draws on a comparative analysis of pension reforms during three periods of government participation of PRWPs: the Schüssel I and II cabinets in Austria (2000-2006), the Rutte I cabinet in the Netherlands (2010-2012) and three pension reforms in Switzerland between 1995 and 2010. The analysis draws on original primary material and interviews.