Although studies of student employment (‘earning while learning’) mostly find positive wage effects, they do not adequately consider the relation of the employment to the field of study. We investigate how different types of student employment during tertiary education affect short- and long-term labour market returns. Beyond examining differences between non-working and part-time working students, we distinguish between student employment related and unrelated to the field of study. Our results show significant positive labour market returns of ‘earning while learning’ only for student employment related to the field of study. These returns consist of a lower unemployment risk, shorter job-search duration, higher wage effects, and greater job responsibility.