Adolescents who attend boarding schools share more time with peers than do students from day schools which, in turn, could provide more opportunities for bullying. Furthermore, some students attend boarding schools because of former social problems. In order to analyse the role of these factors, we examined the bullying behaviour of 706 German adolescents at boarding and day schools in a cross-sectional design. Adolescents at boarding schools showed higher levels of bullying by comparison to adolescents in day schools. Elevated levels of overt bullying in boarding schools could be explained by selection effects. In addition, more time spent with peers was associated with elevated levels of relational victimization. Furthermore, being overtly bullied showed stronger negative associations with life-satisfaction in students from boarding school than in students living at home.