Studies comparing individuals with loss of control (LOC) eating who do and do not have objectively large binge episodes have found that degree of LOC is more important than binge size to psychological and behavioral outcomes. However, the relative importance of these characteristics has not been investigated in a population with binge eating disorder (BED), who by definition all have objectively large binge episodes. Persons with BED and higher weight (N = 34) were enrolled in a BED treatment trial and completed the Loss of Control Over Eating Scale, the Eating Disorder Examination, and measures of eating behavior, mood, and quality of life. Body mass index (BMI) was calculated from measured height and weight. The size of the largest binge episode (measured in kilocalories) and degree of LOC were entered into multiple regression equations to determine their relationships with disordered eating symptoms, depression, quality of life, and BMI in this pilot study. Greater LOC had a stronger independent association than binge size with higher total eating psychopathology, shape dissatisfaction, hunger, food cravings and food addiction symptoms. Larger binge size had a stronger independent association than LOC with higher weight concern and lower general and social quality of life. Both characteristics were associated with higher eating concern and neither were associated with depression or BMI. Both binge size and degree of LOC are associated with important psychosocial treatment targets in patients with BED. Future research should validate the largest binge episode measurement method and replicate the present findings in a larger sample.