Foreigners, including displaced persons, often have limited health-care access, especially to HIV services. Outcomes of antiretroviral therapy (ART) in South Africans and foreigners were compared at a Johannesburg non-governmental clinic. Records were reviewed of 1297 adults enrolled between April 2004 and March 2007 (568 self-identified foreigners, 431 South Africans citizens and 298 with unknown origin). Compared with citizens, foreigners had fewer hospital admissions (39%, 90/303 versus 51%, 126/244; P < 0.001), less missed appointments for ART initiation (20%, 39/200 versus 25%, 51/206; P < 0.001), faster median time to ART initiation (14 versus 21 days, P = 0.008), better retention in care (88%, 325/369 versus 69%, 155/226; P < 0.001) and lower mortality (2.5%, 14/568 versus 10%, 44/431; P < 0.001) after 426 person-years. In logistic regression, after controlling for baseline CD4 count and tuberculosis status, foreigners were 55% less likely to fail ART than citizens (95% CI = 0.23-0.87). These findings support United Nations High Commissioner for Refugees recommendations that ART should not be withheld from displaced persons.