Cognitive behavioral therapy (CBT) is a well-established treatment for anxiety disorders. However, few efforts have been made to summarize the impact of specific intervention-related variables on therapeutic outcomes in different-aged youth with a separation anxiety disorder (SAD). PRISMA guidelines were followed to provide an efficacy overview of different disorder-specific CBT protocols against transdiagnostic ones among youth with SAD. Literature search was conducted in Pubmed, EBSCOhost, PsychInfo, PsycArticles, PSYNDEX, Medline, and ERIC. In total, 9 papers met the eligibility criteria. Overall, preschoolers benefited more from disorder-specific CBT protocols, whereas school-aged children and adolescents from transdiagnostic ones. Interventions aimed at removing SAD maintenance factors, by including parent-sessions, were efficacious, especially among younger children. Psychotherapy had higher efficacy than drug treatments, with individual- and group-CBT addressing SAD symptoms similarly. Findings support CBT as the golden standard for SAD in youth, impacting on the core symptoms in a time-limited, goal-directed way, with long-term effects.