Alcohol use remains a large part of collegiate life and is a major public health concern. Alcohol use generally peaks during the early twenties and declines with age. These declines, referred to as "maturing out," are presumed to be the result of the acquisition of adult roles (e.g. marriage, parenthood, employment) incompatible with alcohol use. Recent empirical evidence suggests that variables other than role transitions (e.g. personality) during emerging adulthood may also be important in understanding this process. Conceptually, changes in identity that occur during emerging adulthood may also be linked to the process of maturing out of heavy drinking, though no studies have yet addressed this possibility. Utilizing data from a large sample of graduating college students during senior year and the two following years (N = 907), the current study examined relations between aspects of emerging adult identity development (identity exploration, instability, self-focus, feeling in-between, and experimentation/possibilities) and drinking outcomes (alcohol use and problems). Using multiple regression, changes in emerging adult identity development accounted for significant variability in alcohol use over and above relationship and employment status. Decreases in experimentation/possibilities significantly predicted decreases in alcohol use. Conversely, increases in feeling in-between significantly predicted decreases in alcohol use. The findings have important implications for both theories of "maturing out" and the development of prevention and early intervention efforts targeting alcohol abuse during this high-risk developmental period.