BACKGROUND: The key objective of our study was to describe the population-average trajectories of wellbeing, spanning the period of 2017-2022, comparing young people with other age groups. Moreover, we aimed to identify subgroups of young people who experienced disproportionate changes in wellbeing. METHODS: We used longitudinal data from six waves (2017-2022) of the Swiss Household Panel. Participants were at least 14 years old in 2017 and had at least one valid composite measure of wellbeing between 2017 and 2022 (n individuals = 11,224; n observations = 49,032). The data were typically collected with telephone or web interviewing. The age of participants ranged from 14 to 102, with a roughly equal distribution of men (51.1%) and women (48.9%). We conceptualized wellbeing as positive affect and life satisfaction, negative affect, stress and psychosomatic symptoms. We described the trajectories of wellbeing using piecewise growth curve analysis. We included sociodemographic characteristics to further describe wellbeing trajectories across subgroups of young people. These comprised (1) gender, (2) migration status, (3) partnership status, (4) living with parents, (5) education/employment status, (6) household income. RESULTS: Young people (age 14-25) experienced a steady decline in positive affect and life satisfaction throughout the entire period, with the greatest change occurring before the pandemic (2017-2019). The trajectories in this outcome were largely stable in other age groups. Moreover, young individuals showed a more pronounced increase in negative affect, particularly in the pre-pandemic years, compared to older groups. Negative affect increased during the pandemic, followed by a subsequent decline post-pandemic, observed similarly across all age groups. Among young people specifically, the trajectory of stress was similar to the one of negative affect. However, issues such as sleep problems, weakness, weariness, and headaches continued to increase in this population from 2017 to 2022. We also found evidence for a greater increase in negative affect during the pandemic in young women and those not in employment or education. CONCLUSIONS: Given the fact that the decline in young people's wellbeing in Switzerland started two years before the pandemic, our study emphasises the importance of consideing their wellbeing within a broader systemic context beyond pandemic-related changes.