Instant messaging (IM) is a communication phenomenon that is fast outstripping other networking tools, such as email and Facebook. Despite this, little is known about the factors that influence employee personal and work-related IM behavior across work and non-work domains. Accordingly, this study examined the influence of relational psychological contract (PC) and psychological contract breach (PCB) on employee IM behavior. Data was collected from 433 IT employees from Iran, Australian, United States and Germany and analyzed using the fuzzy-set qualitative comparative technique. Contrary to our hypotheses, we found that relational PC and PCB related to personal IM use at work. However, we also found that when employees with relational PC are more likely to offset personal IM at work by engaging in work-related IM during non-work time. Thus, our finding provides a new perspective on personal IM at work, which has traditionally been considered a form of cyberloafing workplace deviance. The theoretical and practical implications of our findings are discussed, along with avenues for future research.