Despite the increasing use of teletherapy, it remains unclear if client outcomes differ between remote and in-person settings and, if they do differ, what factors might contribute to these differences. The current study synthesized findings on the comparison between teletherapy and in-person therapy using a meta-analytic approach. All known RCTs comparing teletherapy (telephone and videoconferencing therapy) to in-person therapy were identified via bibliographic database search (PsycINFO, Medline, and Cochrane database), manual searches of previously published meta-analyses, and expert contact. We identified 1,393 studies in the initial search, 20 of which satisfied study inclusion criteria. No significant difference was found between teletherapy and in-person therapy in treatment outcomes at posttreatment (g = −0.043) or follow-up (g = −0.045) or in attrition rates (RR = 1.006). Trainee therapists experienced greater client attrition rates in teletherapy than did licensed therapists. Videoconferencing therapy was at greater risk for client attrition than telephone therapy. Within-group findings showed that teletherapy produced a symptom reduction of a large magnitude at posttreatment (g = 1.026) and follow-up (g = 1.021). These findings provide empirical support for the practice of teletherapy and that client outcomes in teletherapy do not differ from in-person versions of treatments. Public Health Significance StatementsTeletherapy produces comparable outcome to in-person therapy. Trainee therapists are at greater risk of client dropout in teletherapy than licensed therapists.