Perinatal depression affects one in four women in low- and middle-income countries. The World Health Organization’s Thinking Healthy Programme (WHO-THP) is an established ‘task-shared’ cognitive-behavioral therapy intervention for perinatal depression. However, efforts to scale up are hampered by overburdened health systems struggling to maintain quality and fidelity. Here, to overcome these challenges, we coproduced with end users a technology-assisted digital version of the THP delivered by lived-experience peers (technology-assisted peer-delivered THP (THP-TAP)). We aimed to evaluate the effectiveness of THP-TAP compared to the established WHO-THP. A single-blind cluster-randomized controlled noninferiority trial was conducted in rural Rawalpindi, Pakistan, with 70 village clusters randomly distributed to the two interventions. From June 2022 to May 2023, we recruited 980 women with perinatal depression registered with primary healthcare centers. The primary outcome was remission from the depressive episode at 3 months postnatal. On assessment of 846/980 (86.3%) participants at 3 months postnatal, the difference in the remission rate was 8.91% with the lower boundary of the one-sided 97.5% confidence interval being 4.25%, larger than the prespecified −10% noninferiority margin (Pnoninferiority < 0.0001). In settings where health systems are weak and overburdened, THP-TAP offers an effective and potentially scalable alternative to the delivery of psychosocial interventions. ClinicalTrials.gov registration: NCT05353491.