Objectives <p>Studies on time perception during meditation have emphasized the role of attentional resources, although memory storage mechanisms have also been highlighted. To investigate the roles of attention and memory in time perception, we compared two meditation styles, focused attention meditation (FAM) and open monitoring meditation (OMM).</p> Method <p>Thirty-two non-meditators judged short and long time intervals prospectively during FAM, OMM, and control condition. Furthermore, after each session, participants retrospectively reported perception of the passage of time (PoT).</p> Results <p>Prospective results showed that overall time estimations during FAM and OMM were shorter than during the control condition. For the short intervals, durations during both FAM and OMM were underestimated compared to the actual intervals, unlike in the control condition. For the long intervals, we found overestimation in all conditions, with durations in FAM less overestimated than in the control and marginally different from OMM, while time estimations in OMM were not different from those in the control condition. Retrospective PoT was experienced as slower during FAM and OMM, while no alteration was perceived during the control condition.</p> Conclusions <p>In line with the two leading theories of time perception, prospective judgments of short intervals suggest the involvement of purely attentional mechanisms, whereas a combined effect of attention and memory seems to influence the estimation of long intervals. Retrospective PoT judgments appear modulated by the overall effort involved in performing the meditation practices. No robust difference emerged between FAM and OMM, possibly because the subtle attentional distinctions between the two meditative states are harder to detect in meditation-naïve individuals.</p> Preregistration <p>This study is not preregistered.</p>