Among well-acquainted people, those high on agentic narcissism are less popular than those low on agentic narcissism. That popularity-difference figures prominently in the narcissism literature. But why are agentic narcissists less popular? We propose a novel answer―the tit-for-tat hypothesis. It states that agentic narcissists like other people less than non-narcissists do and that others reciprocate by liking agentic narcissists less in return. We also examine whether the tit-for-tat hypothesis generalizes to communal narcissism. A large round-robin study (N = 474) assessed agentic and communal narcissism (Wave 1) and included two round-robin waves (Waves 2-3). The round-robin waves assessed participants’ liking for all round-robin group members (2,488 informant-reports). The tit-for-tat hypothesis applied to agentic narcissists. It also applied to communal narcissists, albeit in a different way. Compared with non-narcissists, communal narcissists liked other people more and―in return―those others liked communal narcissists more. Our results elaborate on and qualify the thriving literature on narcissists’ popularity.