In this study, we examine how student employment impacts higher educational trajectories in France. Focussing on undergraduates' educational outcomes, we show the consequences of different intensities and levels of recurrence of student employment on perseverance in higher education. We use data from a nationally representative four-year longitudinal survey, descriptive analysis and logistic regression are performed to control for student characteristics. Our results suggest that student employment, especially when intensive and during periods of exams, increases exam failure. When it is recurrent over time, student employment often leads to university dropout. Furthermore, even for those who do manage to reconcile work and study, it lengthens the time spent in higher education. This consequence is particularly costly in France, where success in higher education is often judged by time-to-completion, encouraging strategies that lead to finishing degree requirements as quickly as possible. This approach is difficult to follow for students who must combine work and study, leading to particularly pronounced costs.