Despite the recognized influence media have over participatory political behaviors, few studies perform systematic and direct cross-national comparisons of news use and its effects on citizenship in different countries. And even fewer studies consider social media news use. By analyzing comparable and concurrently collected survey data from the United States and the United Kingdom, this study explores how traditional media use and the use of social media for news impact citizens’ political engagement in both nations. Despite differences in terms of media use, political knowledge, political efficacy, and political participation, evidence in both cases confirms the meaningful role social media play in promoting citizens’ political engagement