We examined the associations between time perspective and mental health outcomes (N = 337; Mage = 22.74, SDage = 5.59; 76% female). Time perspective included multiple dimensions (feelings, frequency, orientation, and relation) and time periods (past, present, and future). Mental health outcomes included depressive symptoms, anxiety, and rumination. To demonstrate the reliability of the time perspective scales, test–retest analyses were completed. Multivariate analyses showed that (a) positive feelings about time were associated with lower anxiety; (b) negative feelings about time were associated with greater anxiety; and (c) more frequent thoughts about the past were associated with greater depressive symptoms and anxiety. Associations remained when controlling for anxiety and depressive symptoms, respectively. Moreover, (a) positive feelings about time were associated with lower rumination; (b) negative feelings about time were associated with greater rumination; and (c) more frequent thoughts about the past were associated with greater rumination. Time perspective scales yielded scores that were moderate to high in test–retest reliability. Findings demonstrate the value of examining separate time perspective dimensions and time periods. Results highlight the role of time perspective in mental health interventions for adults.