Changes in the labor market and employment contracts over the past several decades and a recent global recession have increased the salience of perceived job insecurity as a risk factor for poor mental health. We use 25 years of prospective data from the Americans' Changing Lives study to examine long-term histories of perceived job insecurity and their link to psychological distress. We build on the prior literature by using a much longer window of exposure and accounting for involuntary job losses over the lengthy observation period. We find that persistent perceived job insecurity is strongly and significantly associated with greater psychological distress among U.S. workers in the latter part of their careers. Moreover, considering histories of exposure reveals more nuance in the sociodemographic characteristics and employment interruptions that predict persistent or intermittent insecurity and that identify contemporary older workers at particular risk.