A longstanding interest in the existence and/or possibility of a European Public Sphere holds that it may help to overcome some of the EU’s democratic deficits. EU politics, it is often argued, requires greater bottom-up engagement and legitimation, which a pan-European public sphere could help provide. Most extant research in this area has focused on (national) broadcast media. Social media, in contrast, is inherently cross-border, multi-lingual, and bottom-up. We ask whether it can provide a platform for the emergence of a European Public Sphere?