In this article, we consider the question of how professionalized the cantonal parliamentarians are and which factors are related to this professionalization. By definition, Swiss parliamentarians exert an occupation in parallel to their mandate. We argue that parliamentarians who spend more time for their mandate have more resources to do so and, more importantly, intend to pursue a political career. In doing so, we analyze data gathered from a survey that was conducted among all Swiss cantonal parliaments in 2014. Our multi-level analysis shows that parliamentarians who run for office at the national level spend significantly more time for their parliamentary mandate than their colleagues. This effect decreases with the parliamentarians’ age. This finding could be relevant in order to understand the career paths of Swiss parliamentarians. In addition, the study contributes to the discussion of the future development of the militia system in Switzerland.