Objective: The objectives were to investigate the characteristics associated with frequent self-weighing and the relationship between self-weighing and weight loss maintenance. Research Methods and Procedures: Participants (n = 3003) were members of the National Weight Control Registry (NWCR) who had lost ≥30 lbs, kept it off for ≥1 year, and had been administered the self-weighing frequency assessment used for this study at baseline (i.e., entry to the NWCR). Of these, 82% also completed the one-year follow-up assessment. Results: At baseline, 36.2% of participants reported weighing themselves at least once per day, and more frequent weighing was associated with lower BMI and higher scores on disinhibition and cognitive restraint, although both scores remained within normal ranges. Weight gain at 1-year follow-up was significantly greater for participants whose self-weighing frequency decreased between baseline and one year (4.0 ± 6.3 kg) compared with those whose frequency increased (1.1 ± 6.5 kg) or remained the same (1.8 ± 5.3 kg). Participants who decreased their frequency of self-weighing were more likely to report increases in their percentage of caloric intake from fat and in disinhibition, and decreases in cognitive restraint. However, change in self-weighing frequency was independently associated with weight change. Discussion: Consistent self-weighing may help individuals maintain their successful weight loss by allowing them to catch weight gains before they escalate and make behavior changes to prevent additional weight gain. While change in self-weighing frequency is a marker for changes in other parameters of weight control, decreasing self-weighing frequency is also independently associated with greater weight gain. Copyright © 2007 NAASO.