Who gets deplatformed? More specifically, why do social media firms designate only some militant organizations as “terrorists,” imposing consequences on the groups and their supporters? There has been little research on which political actors are removed from tech platforms, despite the importance of this topic. Militant organizations use social media for recruiting, fundraising, and other necessities, so being banned is costly. We build an argument drawing on comparisons to governmental terrorist designation policies, but highlighting firms’ profit motivation. Empirically, we examine organizations in the “Terror” category of the Facebook/Meta Dangerous Organizations and Individuals list. Analyses of hundreds of militant organizations suggest that groups are more likely to be declared terrorists if they are especially violent, Islamist, already designated by prominent countries (using multiple measures, including an original index), or operating in a country with many Facebook users. The findings contribute to debates about intersections of technology, politics, and political violence.