Research investigating what shapes young people’s drinking habits is of great importance. This study aimed to analyse the relation between close social networks and adolescents’ drinking habits and the extent to which close social networks may explain differences in binge drinking among social groups. Data from the ‘Stockholm Survey 2012’ were analysed. The Stockholm Survey was a census survey administered to students in academic years 9 and 11, with a response rate of 76%. Ordered logit models were used to estimate relations between the frequency of binge drinking and the independent variables. Parental educational level is associated with adolescent binge drinking, as students with more highly educated parents are more frequent binge drinkers. Parents’ willingness to offer their teenagers alcohol and peers’ drinking habits are also associated with adolescent binge drinking, with a more permissive parental attitude and a prevalence of drinking among peers increasing the risk. Both parents’ willingness to provide alcohol and peers’ drinking habits may statistically explain a large portion of the observed differences in adolescent drinking by parental education. Close social networks are an important factor influencing adolescent binge drinking, and they may explain a large portion of the differences between social groups.