“Fear of Missing Out” (FOMO) is an all-consuming feeling that is associated with mental and emotional stress. Such strains are caused by a compulsive concern that one is missing an opportunity for a socially rewarding experience often spotted on social media networks. While several personality and psychological factors have been empirically validated as correlated with FOMO, so far, little research has examined the effects of perceived group centrality (i.e., the extent to which group members feel included in the group) and fear of social exclusion on FOMO. Therefore, this study is aimed at examining the mechanism that links these socially driven factors and the need to belong with social media use and, consequently, FOMO, using structural equation modeling. A total of 490 college students ( mean   age = 20.56 , SD = 1.44 ) completed a self-reported questionnaire that included measures of FOMO, the need to belong, social media use, perceived centrality, and fear of social exclusion. The need to belong emerged as the best predictor of FOMO, increasing it both directly and indirectly through the significant mediation of social media use. Females reported a greater need to belong and consequently more FOMO. Females also reported greater use of social media and greater perceived group centrality. Perceived centrality increased FOMO through social media use, but this indirect effect was not significant.