Abstract Background The aim of this systematic review was to evaluate the effectiveness of telephone-administered psychotherapy for depression in adults when compared to control conditions or other active treatments, and to determine adherence to telephone-administered psychotherapy. Methods A bibliographic search was conducted in MEDLINE, Embase, PsycINFO, the Cochrane library, and a number of sources of grey literature. We included randomised controlled trials (RCTs) examining the impact of telephone-administered psychotherapy on depressive symptomatology. Two reviewers independently screened citations, extracted the relevant data, and assessed risk of bias using Cochrane tools. Random effects meta-analyses were used to determine the average effect of the interventions on depressive symptomatology: main analysis including randomised trials only, and several exploratory subgroup and sensitivity analyses. Results We identified ten trials. Telephone-administered psychotherapy showed beneficial effects on depression severity when compared to control conditions ((standardized mean difference [SMD]= −0.85 (95% CI −1.56 to −0.15)). When compared to active comparators, the meta-analysis showed a non-significant small effect size (SMD= −0.18 (95% CI −0.45 to 0.09)), in favour of telephone-administered psychotherapy. Total weighted mean adherence was 73%. Limitations Some of the included studies presented a small sample size. Due to variations in time points follow-ups among the studies, it was not possible to determine long term post intervention effects. Conclusions Available evidence suggests that telephone-delivered psychotherapy may be an effective strategy to reduce depression symptoms when compared to control conditions, and shows an adequate treatment adherence. Future research is needed to determine its cost-effectiveness and long-term effects.