The aim of this 3-wave prospective study was to test impulsivity-related and anxiety-related traits and drinking motives as predictors of alcohol consumption during Orientation Week (O-Week), and the first six months of university life in on-campus college residents. Students from two residential colleges (N = 255, 34.5% female) completed surveys of drinking frequency and quantity for the week prior to university entry, during O-Week, 3 and 6 months later. A brief personality screen for impulsivity, sensation-seeking, anxiety sensitivity and hopelessness was administered along with measures of drinking motives and alcohol consumption. Using moderated mediation analyses and multilevel modeling, impulsivity was found to be the best predictor of drinking variability at O-Week with enhancement motives mediating the effect. This mediated effect was moderated by gender with the indirect effect only occurring for women. Impulsivity was also predictive of drinking change over 6 months, with high impulsive students maintaining heavier levels of drinking (even when controlling for gender). The findings of this study further supports impulsivity as a consistent predictor of student alcohol misuse, even in environments with strong pro-drinking cultures.