To what extent does maternal and paternal autonomy support enhance well-being across the major transitions of high school? We tested the degree to which perceived autonomy supportive parenting facilitated positive changes in self-esteem and life satisfaction and buffered against negative changes in depressive symptoms and school related burnout in 3 Finnish longitudinal studies, each with a measurement point before and after a major transition (middle school, N1 = 760, 55.7% girls; high school, N2 = 214, 51.9% girls; post high school, N3 = 858, 47.8% girls). Results showed that perceived parental autonomy support was negatively related to depressive symptoms and positively related to self-esteem. The findings for the effects on depressive symptoms were replicated across all 3 transitions, while effects on self-esteem were only found for the high school and post high school transitions. Moreover, evidence of coregulation was found for depressive symptoms. Depressive symptoms before the transition were found to decrease autonomy support after the transition for both the high school and post high school transitions. Maternal and paternal autonomy support was of equal importance. Importantly, the effects on depressive symptoms increased as children developed, suggesting the continual importance of parents throughout high school and into emerging adulthood.