Background: Leaving school is an important time for adolescents, with increasing autonomy and developing adult identities. The present study sought to shed light on the content and emotional impact of worries amongst adolescents with and without intellectual disabilities (IDs) at this time of change. Methods: Twenty-five adolescents with mild to moderate IDs and 27 adolescents without IDs, aged 15 to 18?years, took part in the study. Participants' worries were elicited using a structured interview. The levels of rumination and distress related to their most salient worries were also examined, along with their self-reported levels of anxiety. Results: Content analysis of the interviews identified differences between the worries of the two groups of participants, with the adolescents with IDs expressing more general worries about failure and personal threat. Level of distress about worries was positively correlated with anxiety in both groups. The adolescents with IDs were significantly more anxious than their non-disabled peers. Conclusions: The differences between the groups' worries may be linked to differences in life experience and expectations. Consideration should be given to the specific worries of adolescents at the stage of leaving school. Doing so may allow solutions for their concerns to be identified, thus easing distress and leading to a less stressful transition.