Objectives To investigate the relationship between mindfulness and aspects of time perspective (TP, i.e., habitual views of past, present, future). Methods We examined cross-sectional associations between an established measure of mindfulness (FFMQ) and an extended version of the Zimbardo Time Perspective Inventory (Swedish ZTPI; S-ZTPI) in a sample with little experience of mindfulness training (n = 212). In addition, we evaluated the effects of two mindfulness-based interventions (a mindfulness instructor course involving 29 participants and a mindful self-compassion program, n = 40 for the intervention group, n = 41 for controls) on mindfulness and measures of TP including an aggregate measure of deviations from a proposed optimal, or balanced, time perspective (DBTP). Results Cross-sectional data were consistent with a model by which part of the relationship between mindfulness and perceived stress is mediated by reduced DBTP. Global mindfulness scores showed the strongest (negative) associations with the S-ZTPI scales Future Negative and Past Negative. Comparisons of pre/post-intervention data revealed significant mindfulness-based intervention-related reductions of DBTP (Cohen's d = − 0.46), with lowered scores on Past Negative and Future Negative and a small increase on Past Positive. Conclusions The results support the notion that a higher level of mindfulness promotes a more balanced time perspective, with a reduced focus on negative aspects of the past and negative anticipations of the future. Relations to repetitive negative thought processes (rumination, worry) and a potential bidirectional influence of mindfulness and aspects of time perspective are discussed.