ABSTRACT This article examines the politicization of Salafism in the UK over the past two decades – shedding light on why and how some Salafi actors, particularly those belonging to Haitham al-Haddad’s network, are increasingly engaging in formal and informal political activities rather than da’wa (missionary work). It is based on more than 70 interviews with British Salafis and 20 months of participant observation within Salafi communities in London between 2017 and 2020, as well as content analysis of Salafi websites and social media. It argues that owing to increased exclusion and marginalization of British Muslims within the British public sphere, some Salafis have begun to organize protests, vote in UK elections, campaign, wage legal battles, and contest the marginalization of British Muslims through the production of counterhegemonic discourses. It draws on counterpublic theory to explain how exclusion from the public sphere can lead to greater political activity by highlighting how counterpublics enable marginalized communities to regroup and train for agitational activities. This article contributes to our understanding of the causes and consequences of the politicization of Salafi actors in European Muslim-minority contexts, as well as to our understanding of the politicization of religious actors more generally.