Objective: The purpose of the study was to explore heterogeneity and differential treatment outcome among a sample of patients with binge eating disorder (BED). Method: A latent class analysis was conducted with 205 treatment-seeking, overweight or obese individuals with BED randomized to interpersonal psychotherapy (IPT), behavioral weight loss (BWL), or guided self-help based on cognitive behavioral therapy (CBTgsh). A latent transition analysis tested the predictive validity of the latent class analysis model. Results: A 4-class model yielded the best overall fit to the data. Class 1 was characterized by a lower mean body mass index (BMI) and increased physical activity. Individuals in Class 2 reported the most binge eating, shape and weight concerns, compensatory behaviors, and negative affect. Class 3 patients reported similar binge eating frequencies to Class 2, with lower levels of exercise or compensation. Class 4 was characterized by the highest average BMI, the most overeating episodes, fewer binge episodes, and an absence of compensatory behaviors. Classes 1 and 3 had the highest and lowest percentage of individuals with a past eating disorder diagnosis, respectively. The latent transition analysis found a higher probability of remission from binge eating among those receiving IPT in Class 2 and CBTgsh in Class 3. Conclusions: The latent class analysis identified 4 distinct classes using baseline measures of eating disorder and depressive symptoms, body weight, and physical activity. Implications of the observed differential treatment response are discussed. (Contains 5 tables and 2 footnotes.)