Abstract Drawing on cognitive appraisal theory and an appraisal perspective of justice, this study investigates how and when coworker incivility impairs employee psychological well-being. We propose and test a moderated mediation model where perceived job stress mediates the negative effect of coworker incivility on psychological well-being, and this indirect effect is buffered by supervisor interpersonal justice. We tested our model across three studies: a three-wave survey establishing mediati