Major depressive disorder (MDD) is one of the leading causes of work-related disability, and accessing telehealth therapies can be a promising modality for workers with MDD. Barriers to accessing in-person mental healthcare, such as limited availability and accessibility in rural and remote communities, financial constraints, and stigma, have highlighted the need for alternative approaches like telehealth. This study investigated the efficacy of telehealth interventions including CBT for adults over 18 diagnosed with MDD. This rapid review and meta-analysis followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines to ensure a transparent methodology. Out of the 2549 studies screened, 19 were incorporated into the rapid review, and of those, 10 were included in the subsequent meta-analyses. Articles were screened independently by two reviewers, with the disagreements reconciled through discussion. A reviewer extracted data from eligible articles. Descriptive statistics and narrative syntheses were used to describe outcomes. Two meta-analyses were conducted to investigate the efficacy of cognitive behavioral therapy (CBT) delivered by telehealth (tCBT). The first compared tCBT to in-person CBT (pCBT). The second meta-analysis compared tCBT to a control group that did not receive CBT or another telehealth-based treatment. Non-CBT interventions investigated within the non-CBT group included somatic rhythm therapy, problem-solving therapy, psychiatry, behavioral activation, and interpersonal psychotherapy. Overall, individuals with MDD who received tCBT showed significant improvement in depression symptoms. However, the efficacy of tCBT compared to non-telehealth control groups varied across studies. The first meta-analysis indicated the magnitudes of effect were similar for both interventions in reducing depression symptoms 0.023 (95% CI -0.120 to 0.166); p = 1.00. In the second meta-analysis, the ratio of means comparing tCBT (0.51 ± 0.14 SD) to the control group (0.68 ± 0.12 SD) exhibited a statistically significant 25% reduction with regard to depression scores (one-sided p = 0.002), favouring tCBT to non-telehealth, non-CBT study groups. Telehealth-based CBT demonstrated positive effects on depression symptoms; it was generally superior when compared to control groups not receiving CBT and was on par with pCBT. The growing mental health burden in the community underscores the need for accessible telehealth services like tCBT. Effective policy formulation and implementation in national health agendas are essential to meet the increasing demand for mental health support.