AbstractIntroductionAll young people seeking assistance from youth alcohol and other drug services require support to help them minimise the harms from their substance use and continue to develop healthy and meaningful lives. A particular focus on young people in residential out of home care (OoHC) highlights the increased risks of substance use, mental health issues and continued vulnerabilities in this group. While in the past, research contrasted this group with young people living at home, this study contrasted young people in OoHC with homeless youths alongside those living with parents.MethodsThe research contrasted these three groups of young people on substance use profiles, mental health and wellbeing and vulnerability to abuse (historic and current) in the Youth Needs Census conducted in Victoria and Queensland over 2013–2017.ResultsThe results demonstrate a clear risk of increased casual and daily methamphetamine use in the homeless youth group and occasional heroin use in the OoHC group. Mental health measures for both the OoHC and homeless youths were worse than the young people living at home. Trauma was similarly higher in these groups, with both historical and ongoing risks of violent crime for homeless youths.Discussion and ConclusionsThe results demonstrate the similar and serious health and wellbeing risks facing both youths in residential OoHC and homeless youths. These results are concerning as one of these groups is ostensibly in the care of the community and government, while the other group is experiencing unstable accommodation and associated physical risks.