Although extensive research has analyzed the factors that moderate economic self-interest—the relationship between individuals’ income position and their preferences for redistribution—there is little crossnational research that analyzes the role of political parties. This article argues that political parties play a considerable moderating role in (de-)activating economic self-interest based on the polarization they display in their economic and cultural positions. By combining the World/European Values Survey, the World Income Inequality Database, and the Comparative Manifesto Project datasets, the analyses estimate the moderating effect of party polarization on economic self-interest. The results suggest that economic polarization enhances self-interest for the poor (respondents below the mean income), even when controlling for income inequality, but not for the rich. Moreover, cultural polarization also appears to reinforce self-interest for the poor, rather than supplanting it. The findings have important implications regarding ability for political parties to activate issues among the public.