Under pressure, people often prefer what is familiar, which can seem safer than the unfamiliar. We show that such favoring of familiarity can lead to choices precisely contrary to the source of felt pressure, thus exacerbating, rather than mitigating, its negative consequences. In Experiment 1, time pressure increased participants’ frequency of choosing to complete a longer but incidentally familiar task option (as opposed to a shorter but unfamiliar alternative), resulting in increased felt stress during task completion. In Experiment 2, pressure to reach a performance benchmark in a chosen puzzle increased participants’ frequency of choosing an incidentally familiar puzzle that both augured and delivered objectively worse performance (i.e., fewer points obtained). Participants favored this familiar puzzle even though familiarity was established through unpleasant prior experience. This “devil you know” preference under pressure contrasted with disfavoring of the negatively familiar option in a pressure-free situation. These results demonstrate that pressure-induced flights to familiarity can sometimes aggravate rather than ameliorate pressure, and can occur even when available evidence points to the suboptimality of familiar options.