Although the literature has focused on individual differences in authenticity, recent findings suggest that authenticity is sensitive to context; that is, it is also a state. We extended this perspective by examining whether incidental affect influences authenticity. In three experiments, participants felt more authentic when in a relatively positive than negative mood. The causal role of affect in authenticity was consistent across a diverse set of mood inductions, including explicit (Experiments 1 and 3) and implicit (Experiment 2) methods. The link between incidental affect and state authenticity was not moderated by ability to down-regulate negative affect (Experiments 1 and 3) nor was it explained by negative mood increasing private self-consciousness or decreasing access to the self system (Experiment 3). The results indicate that mood is used as information to assess one's sense of authenticity.