Since the advent of mass media, ‘going public’ has been a key tool in the strategic inventory of presidents seeking to promote their policies to politicians and the public. Over the last decade, social media has offered presidents and their office with a new platform to address the nation directly without relying on traditional media gatekeepers. Nevertheless, both ‘going public’ strategies and presidents’ use of social media have almost exclusively been researched in the context of the presidential systems. The aim of this article is to extend research and offer the first systematic study of presidential Twitter use in European semi-presidential systems. We conceptualise presidential Twitter use as a form of presidential activism that is complementary to the use of formal powers or informal attempts to influence policy. Whereas the latter are driven by institutional or partisan conflict, going public strategies and presidential Twitter use primarily address societal concerns and, hence, are motivated by contextual factors outside the core realm of party politics. Instead, we should expect social conflict and societal grievances to determine demand and supply of presidential Twitter use. We test our propositions using a new dataset of tweets by presidents in European semi-presidential systems 2010–2020.