Background: Young people with autism spectrum conditions (ASC) face many educational challenges, particularly in terms of academic achievement, social inclusion, and mental health. School connectedness is linked to many positive outcomes and may be of particular salience at the primary-secondary school transition, when young people with ASC are expected to cope in new and unfamiliar settings. Aims: This study explores for the first time school connectedness across the primary to secondary school transition for young people with ASC. Sample: Twenty-eight students with ASC (23 male, five female) and a comparison group of 21 students with no additional needs (16 male, five female) participated. Methods: A longitudinal design was used to measure school connectedness across transition at four time-points from the end of primary school, into the first and second years of secondary school. Students completed the Psychological Sense of School Membership (Goodenow, 1993, Psychology in the Schools, 30, 79) questionnaire at each time-point, with responses analysed statistically. Results: Students with ASC reported positive levels of school connectedness across transition, although their scores remained lower than those of their typically developing peers. The gap between the two groups narrowed significantly during the first year of secondary school, with students in the ASC group reporting improving levels of school connectedness, although there were non-significant signs of a decline for both groups in the second year. Conclusions: Transition can be a positive experience for students with ASC. However, their consistently lower levels of school connectedness compared to those of their peers highlight the need for ongoing monitoring and support during secondary education.