Why do governments ban some extremist organisations and not others? To answer this question, this article investigates the banning of far-right groups in Germany, the archetype of ‘militant democracy’, where there are laws and institutions that protect a state’s democratic order through selective and qualified restrictions of certain political rights. The study draws on data about far-right organisations mentioned in federal security agency reports since 1990. Two-step fuzzy-set qualitative comparative analysis (QCA) reveals that situations of high far-right visibility are necessary to take banning action. Within such situations, there are four sufficient combinations of organisational conditions that lead to banning action: Germany has imposed bans on neo-Nazi groups, longstanding organisational hubs in the far-right scene, aggressive militant organisations, and neo-Nazi sham parties. Two follow-on case studies identify related causal mechanisms underlying these sufficiency patterns. The article shows that Germany’s militant democracy practices are not applied as a matter of principle to every far-right organisation susceptible to a ban, but rather are used more pragmatically. This pragmatic approach implies that state actors should be especially attentive to the efficacy of using bans to disrupt and diminish extremist threats. Although there is some evidence of state actors considering efficacy, there are also indications that banning is sometimes a tool of politics rather than a targeted response to threats.