Abstract: | When does social support alleviate or exacerbate the effects of being excluded by colleagues in the workplace? This study integrates belongingness and social support theories to predict and demonstrate the differential effects of work‐related support (i.e., perceived organizational support; POS) and non‐work‐related support (i.e., family and social support; FSS) on employee reactions to co‐worker exclusion. Consistent with our predictions, we found that employees reporting high levels of co‐worker exclusion and high levels of perceived organizational support demonstrate higher levels of performance and increased levels of self‐worth than those reporting low levels of POS. Alternatively, support from family or friends intensified the negative relationship between co‐worker exclusion and self‐esteem and the positive relationship between co‐worker exclusion and job‐induced tension. Unexpectedly, FSS did not influence the supervisor‐rated task performance of excluded workers, nor did POS mitigate the relationship between co‐worker exclusion and job‐induced tension. Implications for theory, research, and practice are discussed. |