High levels of moderate-to-vigorous physical activity (MVPA) are strongly correlated with long-term weight loss maintenance, however few studies have examined sedentary behavior (SB) in successful weight loss maintainers (WLM). Our aim was to compare MVPA and SB in successful WLM (maintaining ≥13.6 kg weight loss for ≥1 y) as compared to both normal weight controls (NC, matched to current BMI of WLM) and overweight/obese controls (OC, matched to pre-weight loss BMI of WLM). 114 adults age 18-65 wore the ActivPAL for 7 days. Participants were excluded from the analysis if criteria for a valid monitoring period were not met (≥3 weekdays and ≥1 weekend day with ≥10 hrs awake). Data from 90 subjects were analyzed (30 WLM, 33 NC, and 27 OC). Age, gender, and ActivPAL wear time were similar across groups. Compared to OC, WLM spend a lower proportion of awake time in SB (WLM 61±9.3%, OC 70±7.5%; p<0.0001), and a higher proportion in light activity (WLM 30±7.9%, OC 25±6.7%; p=0.0099). Compared to both NC and OC, WLM spend significantly more minutes/day in MVPA (WLM 95±40, NC 69±20, OC 56±20; p<0.0001). Findings indicate that not only do WLM spend more time in MVPA than both OC and NC, but compared to OC, they also spend 8.5% (58 min/day) less time sedentary and 4.7% (55 min/day) more time in light activity. Our data indicate that it may be important to decrease sedentary time as well as increase physical activity (light and MVPA) in order to achieve long-term weight loss maintenance.