In this study, we explored the antecedents, consequences, and boundaries of group affective tone. Specifically, we tested the relationships between team member's personality traits (i.e., team agreeableness, extraversion, and neuroticism) and group affective tone, the relationship between group affective tone and individual-level job performance, and the moderating effects of team social interdependence and perceived social loafing. We collected data from 94 sales teams, and conducted a series of hierarchical regression/hierarchical linear modeling analyses to test our hypotheses. The results showed that team members' mean levels of extraversion and agreeableness were positively related to positive group affective tone, while team members' neuroticism was positively related to negative group affective tone. In addition, both social interdependence and perceived social loafing moderated the relationships between team personality and group affective tone in different ways. Finally, positive group affective tone had a positive effect on individual-level job performance.