The overall purpose of this study is to advance the current social media literature by providing insights into the causal patterns of psychological factors underlying individuals’ social media usage behaviors. Based on trait theory, the authors analyze what constellations of the Big five personality traits predict social media usage in terms of liking, sharing, and commenting behaviors. This article presents the results of a study with 1285 users of a major online social media platform. The data are analyzed using fuzzy set qualitative comparative analysis (fsQCA). The results indicate that there exist multiple personality structures predicting social media usage. These insights help managers define segmentation approaches and develop user management strategies.