Pregaming represents a uniquely high-risk drinking event for young adults, and subfacets of impulsivity are robust predictors of alcohol use and related negative outcomes. Further, it is likely that pregame events contain social and physical stimuli that are particularly appealing for impulsive individuals, thus exacerbating risk for negative outcomes. However, no prior studies have investigated the extent to which impulsive personality traits interact with pregame events to confer alcohol-related risk. Thus, the present study examined the extent to which UPPS-P (urgency-perseverance-premeditation-sensation seekingpositive urgency) subfacets of impulsivity interact with the occurrence of pregaming to predict relations between pregaming, drinking quantity, and negative alcohol-related outcomes. College students (N = 737) completed a modified, online version of the 30-day Timeline Followback in which they reported drinking quantity, negative consequences, and whether they engaged in pregaming on a given day. Results indicated that sensation seeking and a lack of premeditation moderated relations between pregaming and drinking quantity such that those who are higher in sensation seeking and lower in their ability to plan ahead drank more on pregaming days. Sensation seeking and positive urgency moderated relations between pregaming and negative consequences such that those who are higher in positive urgency experience more consequences on pregaming days whereas those who are higher in sensation seeking experience less consequences. Future studies may benefit from more granular assessments of pregame-related risk as subfacets of impulsivity may confer momentary risk. Prevention efforts targeting the reduction of pregaming frequency, particularly among impulsive individuals, may lower overall risk for heavy drinking.