Work interruptions have made significant inroads into the knowledge workers’ nonwork domain, in large part due to the ubiquitous nature of mobile devices that blur the work–nonwork boundaries by enabling work interruptions anywhere and at any time. We examine the effects of such technology-mediated work-related interruptions that occur during one’s time off on both work and nonwork outcomes. Leveraging theoretical perspectives from interruption, work–life interface, and conservation of resources, we conceptualize both positive and negative effects of such interruptions on behavioral and psychological outcomes. We identify three mediating mechanisms via which these effects occur: interruption overload and psychological transition via which negative effects occur and task closure via which positive effects occur. Results reveal significant effects of interruptions on work and nonwork outcomes through the three mediating mechanisms. Although positive effects are observed, the total effects of work-related interruptions are detrimental across both work and nonwork outcomes, with the strongest negative effect on work exhaustion. The results suggest that after-hours work interruptions do not necessarily benefit work performance and come at the cost of work exhaustion. Analyses also reveal that the effects of interruptions are dependent on the technology via which these occur. While phone and messaging generate negative outcomes through interruption overload, e-mail leads to both positive and negative outcomes through task closure and psychological transition respectively. The study concludes with implications for research and practice on how to mitigate negative effects and enhance positive effects.