People differ in the extent to which they experience positive (PA) and negative affect (NA) rather independently or as bipolar opposites. Here, we examine the proposition that the nature of the relation between positive and negative affect in a person’s emotional experience is indicative of psychological well-being, in particular the experience of depressive symptoms, typically characterized by diminished positive affect (anhedonia) and increased negative affect (depressed mood). In three experience sampling studies, we examine how positive and negative affective states are related within people’s emotional experience in daily life and how the degree of bipolarity of this relation is associated with depressive symptom severity. In Study 1 and 2, we show both concurrently and longitudinally that a stronger bipolar PA–NA relationship is associated with, and in fact is predicted by, higher depressive symptom severity, even after controlling for mean levels of positive and negative affect. In Study 3, we replicate these findings in a daily diary design, with the two conceptually related main symptoms of depression, sadness, and anhedonia, as specific manifestations of high NA and low PA, respectively. Across studies, additional analyses indicate these results are robust across different time scales and various PA and NA operationalizations and that affective bipolarity shows particular specificity toward depressive symptomatology, in comparison with anxiety symptoms. Together, these findings demonstrate that depressive symptoms involve stronger bipolarity between positive and negative affect, reflecting reduced emotional complexity and flexibility.