In Switzerland, initial vocational education and training graduates may enter a track of the tertiary system called professional education. Professional education represents about one-third of the tertiary system, includes numerous vocational training courses, and prepares for managerial or expert positions. Despite its prevalence, the long-term returns to professional education have rarely been investigated due to lacking data. In order to fill this gap, we will estimate the long-term returns to professional education based on a novel methodological design. Secondly, we aim to explain the differences in the returns to professional education between occupational fields by making use of the task-based approach of Autor, Levy and Murnane (2003). Analyses are based on the Swiss Labour Force Survey from 1991–2016. Based on a quasi-panel with cohort fixed effects and on linear regression models, our results reveal average short-term returns to professional education of 7% and long-term returns of 11%. However, we find considerable differences in the returns between training fields, which can partly be attributed to differences in the change of task composition after completion of professional education between occupations.