Background No previous study has determined whether there are differences in the youth appeal of alcohol advertisements for popular versus unpopular brands among underage drinkers. This paper provides a systematic investigation of the differential appeal of brand-level alcohol advertisements among underage youth and young adults in the U.S. Methods We examined three issues of eight magazines popular among underage youth. From the advertised alcohol brands, we selected the ads for the top 10 and bottom 10 brands by prevalence of underage youth consumption, based on the results of a previous national survey. We assessed the ads’ appeal using a sample of 211 students recruited from one graduate and two undergraduate courses at Boston University. Respondents rated the appeal of each advertisement on four dimensions: physical and social appeal, appeal to underage youth, perceived effectiveness, and liking. Using random effects linear regression, we compared the appeal of advertisements for popular versus unpopular brands. Results On each dimension, the ads for popular youth alcohol brands were rated as significantly more appealing than the ads for unpopular brands. The magnitude of this difference was 0.26 standard deviations for the physical and social appeal score, 0.25 for the appeal to underage youth score, 0.21 for the perceived effectiveness score, and 0.16 for the liking score. Conclusions Advertising for alcohol brands that are popular among youth contain elements that are more likely to appeal to underage youth and young adults than ads for brands that are relatively unpopular among young drinkers.