Positive epidemiology highlights the importance of considering positive mental health, which allows young people to navigate life’s challenges effectively. In this research snapshot, the LifeCourse team investigated whether positive mental health during early adolescence contributed to better outcomes in late adolescence, during the first year of the COVID-19 pandemic. High levels of positive mental health in early adolescence reduced the risk of psychological distress and increased life satisfaction during the COVID-19 pandemic. However, it did not influence sleep or alcohol use. These findings highlight the importance of measuring the strengths and resources that protect young people’s health at a population level.