Poor academic performance is known to be linked to the tendency to procrastinate. The latter is thought to reflect deficits in effort regulation and study time management (i.e. learning-related resources), but some recent results have suggested that it could stem from psychological inflexibility. The main objective of the present study was thus to ascertain whether effort regulation, study time management, and psychological (in)flexibility predict variations in French students' academic procrastination. The results of an online survey among 259 first-year humanities and social sciences students revealed that 42.4% of the variance in procrastination was predicted by effort regulation and study time management, and 4% by psychological inflexibility. There was also a negative relationship between academic performance and procrastination. These results are discussed in terms of the usefulness of implementing interventions at the start of university to promote academic success and student wellbeing.