Despite a growing literature on college students' sexual behaviors, little is known about how sexual behaviors, and their associations with alcohol, differ for college and noncollege attenders, and whether these patterns represent changes during college or an extension of pre-college behaviors. This paper applied time-varying effect models to data from the National Longitudinal Study of Adolescent to Adult Health to examine (1) prevalence of four sexual behaviors from ages 14 to 24 and (2) how their association with frequent heavy episodic drinking varied across these ages for college and noncollege attenders. Nonattenders have higher prevalence of all sexual behaviors than college attenders across most ages; however, the association between heavy episodic drinking and sexual behaviors is stronger for college attenders during ages 18-20.