HIV counselling and testing (HCT) is a critical component of HIV prevention and treatment efforts. Between April 2010 and June 2011 South Africa ran an ambitious, multi-sector, campaign aiming to test 15 million people nationwide. We assessed the extent to which this campaign reached (1) those who previously had never tested for HIV and (2) high risk and socioeconomically vulnerable populations. We used data from the National Income Dynamics Study (NIDS, n=18,650), a nationally representative panel study in South Africa, to assess the uptake of first-time testing between 2010 and 2012 at the national level and by age, gender, racial, and province-level subgroups. Multivariate logistic regression analyses were used to compare the factors associated with HIV testing in 2010 and 2012, and to assess the characteristics of first-time testers. The proportion of adults having ever received an HIV test increased from 43.7% (95% CI: 41.48; 45.96) in 2010 to 65.2% [63.28; 67.10] in 2012, as approximately 7.5 million individuals 15 years and older tested for the first time nationally. However, there was large variation in new testing rates across geographic areas and population subgroups. The association between ever testing and both income and self-reported health declined between 2010 and 2012, suggesting the campaign was successful in reaching poorer and healthier individuals. However, disparities in testing by education and gender remained strong between 2010 and 2012. The provision of HCT services in South Africa led to a steady rise in the proportion of individuals ever tested for HIV and has improved equity of HCT uptake. Future initiatives to increase HCT uptake, both within South Africa and in other countries, would gain from lessons learned from the South African effort. However, new interventions may be required to improve testing rates among the less educated and men, particularly poor men, and to achieve universal HCT access and uptake.