Objective: Many students pregame (ie, drink before drinking), but there are scant data evaluating changes following college entry. The authors examined pregaming across the fall quarter and identified predictors of change and initiation in college. Participants: Freshmen ("N" = 708; 53% female, 100% drinkers) were recruited during university orientation (baseline). Methods: Self-report data were collected at baseline and end of fall quarter for 3 cohorts (the 2008-2010 academic years) and included demographics, alcohol use, problems, pregaming, personality, and expectancies. Results: Pregaming increased from 61.7% (baseline) to 79.9% (follow-up), with students pregaming twice as often and attaining higher blood alcohol concentration at follow-up. Many (54%) baseline non-pregamers initiated by follow-up. Initiation was associated with increased overall drinking (including heavy episodic drinking), positive expectancies, and greater behavioral activation sensitivity. Conclusions: Pregaming rapidly escalates upon college entry and students who initiate in college may be at higher risk for alcohol-related problems. Campus prevention and intervention efforts should consider including pregaming in their prevention programming. (Contains 3 tables and 1 figure.)