Background: The present study's aim was to examine the long-term effects (8 to 13 years post-treatment; M = 9.83 years; SD = 1.71) of the most widely used treatment approaches of exposure-based cognitive behavioral treatment for phobic and anxiety disorders in children and adolescents (i.e., group treatment and two variants of individual treatment). An additional aim was to compare the relative long-term efficacy of the treatment approaches. Method: At long-term follow-up, participants (N = 67) were between 16 and 26 years of age (M = 19.43 years, SD = 3.02). Primary outcome was the targeted anxiety disorder and targeted symptoms. Secondary outcomes were other disorders and symptoms not directly targeted in the treatments including (1) other anxiety disorders and symptoms, (2) depressive disorders and symptoms, and (3) substance use disorders and symptoms. Results: Long-term remission for anxiety disorders and symptoms targeted in the treatments was evident 8 to 13 years post-treatment. Long-term remission also was found for the secondary outcomes. There were more similarities than differences in the long-term gains when comparing the treatment approaches. Conclusions: Consistent with past research, the study's findings provide further evidence that the short-term benefits of exposure-based CBT for childhood phobic and anxiety disorders using both group and individual treatment may extend into the critical transition years of young adulthood.