OBJECTIVE: Extensive antiretroviral therapy scale-up is expected to prevent onward transmission of HIV by reducing the overall community viral load. Despite multiple studies about predictors of detectable viral load derived from clinical setting, to date, no study has established such predictors using a population-based viral load survey in a sub-Saharan African hyperendemic setting to inform interventions designed to halt HIV transmission. We used one of Africa's largest prospective cohorts in rural KwaZulu-Natal Province, South Africa, to establish the key sociodemographic, behavioral and community predictors of unsuppressed viral load at the population level. METHODS: We collected 5454 viral load measurements from a population-based viral load survey of 3892 women living with HIV from a rural population during 2011, 2013 and 2014. Multilevel logistic regression models were fitted to examine the risk predictors of unsuppressed viral load. RESULTS: Among women living with HIV in this population, the prevalence of unsuppressed viral load was 69% in 2011, 58% in 2013 and 53% in 2014. Although time since HIV infection was associated with lower risk for virologic detection [adjusted odds ratio (aOR) = 0.91,0.87-0.94], young women (aOR = 2.59,1.47-4.55) with extensive external migration history (aOR = 1.25,1.02-1.54), greater number of sexual partners (aOR = 1.30,1.02-1.67), and longer history of residing in an HIV incidence hotspot community were more likely to experience unsuppressed viral load (aOR = 1.12,1.06-1.19). CONCLUSION: Young women, number of sexual partners, transiency and longer residence in an HIV hotspot community are important determinants of unsuppressed viral load in a hyperendemic rural African setting. To substantially reduce the persistently high transmission potential in these settings, targeted interventions to address these risk factors will be essential for both individual and population health gains.