According to balance theory (Heider, 1958), when 2 coworkers develop different levels of leader-member exchange (LMX) relationships with their supervisor, a triadic relational imbalance will arise among the 3 parties that may result in hostile sentiments and poor social interactions between them. This study examines the consequences and psychological processes of (dis)similar levels of LMX on the interpersonal interactions between coworkers. Using data from 2 independent studies, the results of social relations analyses show that (a) actual (dis)similarity in LMX between Coworkers A and B increases Coworker A's feelings of contempt for Coworker B and decreases Coworker A's perception of help received from Coworker B (Study 1); (b) Coworker A is more likely to experience contempt for Coworker B when Coworker A perceives that he/she has a higher or lower level of LMX compared to Coworker B than when Coworker A perceives that his/her level of LMX is similar to Coworker B's (Study 2); and (c) these relationships only hold true for employees with a high social comparison orientation (SCO) in both Studies 1 and 2. Particularly, in Study 1, we also show that contempt is a crucial mediator that transmits the interactive effect of LMX (dis)similarity and SCO on perceptions of help received from coworkers. Furthermore, an average level of perceived help from coworkers is positively related to the sales performance of individual employees.