The Information-Motivation-Behavioral skills (IMB) model has been a useful tool for understanding sexual risk behavior. However, its utility in predicting sexual risk behaviors among bar patrons, for whom the bar setting poses a higher risk of alcohol-related sexual risk behavior, has been underexplored. We assessed (1) the extent to which the IMB predicted number of episodes of unprotected sex in the past six months and (2) whether incorporating sex under the influence of alcohol and alcohol use improved the predictability of the model among bar patrons. Hierarchical regression models were conducted on data from 406 men and women from bars in rural areas of North-West province, South Africa. Behavioral skills were the sole IMB variable to predict unprotected sex with main partners (β = - 0.40; p < .001), explaining 18% of the variance. Variance explained increased to 21% with addition of sex under the influence of alcohol (β = 0.13; p = .019) and further increased to 26% with the addition of alcohol use (β = 0.24; p < .001). Motivation (β = - 0.21; p = .006) and behavioral skills (β = - 0.21; p = .006) were the significant IMB predictors of unprotected sex with casual partners (explaining 15% of the variance). Variance explained increased to 22% with the addition of sex under the influence of alcohol (β = 0.26; p = .001), but alcohol consumption was not an independent predictor of episodes of unprotected sex with casual partners. Interventions for improving HIV prevention behaviors among bar patrons should focus on enhancing individuals' behavioral skills and motivation and reducing their alcohol consumption.