This research examines how the implications of emotional labor cantransfer from customer encounters to coworker interactions using temporallylagged data from a sample of frontline service employees. Theresults show that surface acting in customer service encounters is positively,and deep acting is negatively, related to ego depletion. Employees’ego depletion, in turn, is positively associated with their interpersonallyharmful behavior toward coworkers. Hence, ego depletion appears as amediating variable that translates the implications of distinct emotionallabor strategies into coworker harming. Moreover, emotion regulationself-efficacy moderates the role of surface acting. The positive indirectrelationship between surface acting and coworker harming, via egodepletion, is buffered among employees with higher emotion regulationself-efficacy. These findings shed new light on the complex andfar-reaching consequences of emotional labor.We demonstrate the relevanceof emotional labor to third parties not directly involved in customerservice encounters and highlight important mediators and boundary conditionsof these indirect relations.