BACKGROUND: In Southern Africa, men access HIV counseling and testing (HCT) services less than women. Innovative strategies are needed to increase uptake of testing among men. This study assessed the effectiveness of incentivized mobile HCT in reaching unemployed men in Cape Town, South Africa. METHODS: A retrospective analysis of HCT data collected between August 2008 and August 2010 from adult men accessing clinic-based stationary and non-incentivized and incentivized mobile services. Data from these 3 services were analyzed using descriptive statistics and log-binomial regression models. RESULTS: A total of 9416 first-time testers were included in the analysis as follows: 708 were clinic based, 4985 were non-incentivized, and 3723 incentivized mobile service testers. A higher HIV prevalence was observed among men accessing incentivized mobile testing [16.6% (617/3723)] compared with those attending non-incentivized mobile [5.5% (277/4985)] and clinic-based services [10.2% (72/708)]. Among men testing at the mobile service, greater proportions of men receiving incentives were self-reported first-time testers (60.1% vs. 42.0%) and had advanced disease (14.9% vs. 7.5%) compared with men testing at non-incentivized mobile services. Furthermore, compared with the non-incentivized mobile service, the incentivized service was associated with a 3-fold greater yield of newly diagnosed HIV infections. This strong association persisted in analyses adjusted for age and first-time versus repeat testing [risk ratio: 2.33 (95% confidence interval: 2.03 to 2.57); P < 0.001]. CONCLUSIONS: These findings suggest that incentivized mobile testing services may reach more previously untested men and significantly increase detection of HIV infection in men.