In contrast to the increased research interest in the benefits of mindfulness and self-compassion, relatively few studies have examined their unique and combined effects in predicting affect. This cross-sectional study examined the predictive value of mindfulness and self-compassion for depressive symptoms, negative affect, and positive affect in a large representative sample of community adults (N = 1736). The Five Facets of Mindfulness Questionnaire (FFMQ) was used as a measure of mindfulness and the Self-Compassion Scale (SCS) as a measure of self-compassion. Five FFMQ facets were explored: observe, describe, act with awareness, non-judgment, and non-reactivity. Two SCS facets were explored: its positive items (SCS Pos) and its negative items (SCS Neg). When simultaneously examining all seven facets of mindfulness and self-compassion, three of the five FFMQ facets and SCS Neg significantly predicted both depressive symptoms and negative affect, with SCS Neg and act with awareness being the strongest predictors. These findings suggest that a harsh attitude towards oneself and a lack of attention when acting have the greatest value in predicting the presence of psychological symptoms. With respect to positive affect, four of the five FFMQ facets (except non-judgment) were significant predictors, with no unique predictive value of the two SCS’s facets, suggesting that mindfulness is a more important predictor of positive affect than self-compassion, as measured by the FFMQ and SCS.