Monitoring HIV treatment with laboratory testing introduces delays for providing appropriate care in resource-limited settings. The aim of our study was to determine whether point-of-care HIV viral load testing with task shifting changed treatment and care outcomes for adults on antiretroviral therapy (ART) when compared with standard laboratory viral load testing. We did an open-label, non-inferiority, randomised controlled trial in a public clinic in Durban, South Africa. We enrolled HIV-positive adults (aged ≥18 years) who presented for their first routine HIV viral load test 6 months after ART initiation. Individuals were randomly assigned by a random number allocation sequence to receive either point-of-care viral load testing at enrolment and after 6 months with task shifting to enrolled nurses (intervention group), or laboratory viral load testing (standard-of-care group). The primary outcome was combined viral suppression (<200 copies per mL) and retention at 12 months after enrolment. A non-inferiority margin of 10% was used. Analysis was done by intention to treat. This study was registered with ClinicalTrials.gov, NCT03066128. Between Feb 24, 2017, and Aug 23, 2017, we screened 657 participants, and 390 were enrolled and randomly assigned to either the intervention group (n=195) or standard-of-care group (n=195). 175 (90%) individuals in the intervention group and 148 (76%) individuals in the standard-of-care group had the primary outcome of retention with viral suppression, a difference of 13·9% (95% CI 6·4-21·2; p<0·00040). 182 participants (93%) in the intervention group had viral suppression compared with 162 (83%) in the standard-of-care group (difference 10·3%, 3·9-16·8; p=0·0025); 180 (92%) and 162 (85%) were retained in care (7·7%, 1·3-14·2; p=0·026). There were no adverse events related to point-of-care HIV viral load testing or task shifting. Point-of-care viral load testing combined with task shifting significantly improved viral suppression and retention in HIV care. Point-of-care testing can simplify treatment and improve outcomes for HIV-positive adults receiving ART in resource-limited settings. National Institute of Allergy and Infectious Diseases.