Social norms are important in explaining why people vote, but where do those norms come from and is social pressure motivated by partisanship? In this article, we use political discussion network data to examine the role of party identification in shaping the relationship between injunctive norms, civic duty and voter turnout. More specifically, we examine the extent to which both the application of injunctive norms and their impact on turnout is affected by shared partisan identification. We find that citizens are more likely to perceive normative pressure to vote from fellow partisans, a phenomenon we refer to as “partisan pressure”. However we do not find consistent evidence for the hypothesis that turnout is more closely related to the approval or disapproval of discussants who share a partisanship. By separating the role of social pressure from that of normative beliefs we also demonstrate that injunctive norms affect voter turnout both directly and indirectly by increasing civic duty.