BACKGROUND: Efficacious treatments for winter seasonal affective disorder (SAD) include light therapy (LT) and cognitive-behavioral therapy (CBT-SAD); however, baseline characteristics may differentially predict treatment outcomes. This study investigated body mass index (BMI) and atypical balance (the proportion of atypical depression symptoms), as predictors of depression remission. METHODS: The parent study randomized 177 adults diagnosed with Major Depression, Recurrent with Seasonal Pattern to 6-weeks of CBT-SAD (n = 88) or LT (n = 89) and followed participants one and two winters later. At baseline, BMI was measured and atypical balance was derived using the Structured Interview Guide for the Hamilton Rating Scale for Depression-Seasonal Affective Disorder Version (SIGH-SAD) as 8-item atypical subscale score/total SIGH-SAD score × 100. Depression remission was defined using standard SIGH-SAD cutpoints. Hierarchical logistic regressions tested the main effects of treatment modality, BMI, and atypical balance and their interactive effects on depression remission at post-treatment and follow-ups. RESULTS: The BMI × treatment and atypical balance × treatment interactions significantly predicted depression remission at second winter follow-up. The probability of remission was higher in CBT-SAD than LT at BMI ≤ 26.1 and atypical balance ≤ 40.3%. This predictive relationship survived when adjusting atypical balance for BMI, but not vice-versa. LIMITATIONS: Participants were predominantly White and older. BMI does not account for muscle mass or fat distribution. CONCLUSIONS: BMI and atypical balance prescriptively predicted higher likelihood of depression remission two winters following CBT-SAD but not LT. This work informs clinical decision-making and precision medicine efforts.