In this paper, we contribute to a growing literature on debt and mental health and ask whether patterns of unsecured debt accumulation and repayment over two decades are associated with depressive symptoms at age 50. Using data from the National Longitudinal Study of Youth 1979 Cohort and group trajectory models, we have three key findings. First, we find substantial heterogeneity in debt trajectories across the life course. Second, respondents who report consistently high debt levels across the life course or who cycle in and out of high debt report significantly more depressive symptoms than respondents who hold consistently low levels of debt. These findings hold for both absolute and relative (debt-to-income) debt. Third, we find that the association between debt and depressive symptoms is strongest among respondents with less than a college degree, but we find less evidence for heterogeneity by race in this cohort.