Difficulties with interpersonal relationships have been reported in children and adolescents with manic symptoms, even if they do not fulfil criteria for a manic episode. The role of social aptitude (SA) in youths with manic symptoms has never been examined in the general population. Moreover, no study has examined whether SA is differentially associated with dimensions of manic symptoms. We hypothesised that youth with predominantly undercontrol manic symptoms (characterised by irritability) would show lower levels of SA; conversely, youth with predominantly exuberant symptoms would show better than average social skills. Our sample comprised 5325 participants from the 2004 British Child and Adolescent Mental Health Survey (B-CAMHS04), mean age 10.3 years, SD = 3.3, 48 % girls. Manic symptoms were assessed with the Development and Wellbeing Assessment by interviewing parents and young people. Children and adolescents with manic symptoms had a lower SA score, compared to the general population by parent report, but not by self-report. SA score was higher in youths with predominantly exuberant manic symptoms compared to the general population; whereas the youths with predominantly undercontrol manic symptoms had lower SA scores by parent and self-report. Our results provide further evidence for the distinction between exuberant and undercontrol manic symptoms and highlight the need to focus on SA in future research.