This article examines the profile of prisoners who do not take part in formal education while being incarcerated (e.g. language or ICT courses) and the barriers to participation these prisoners experience. Survey data were collected as part of a research project conducted in a remand prison in Belgium (n = 486). The results demonstrate that 29% of the prisoners take part in educational courses and that participation rates are lower among Belgian and non-European prisoners, those with either a very good or very poor understanding of the Dutch language, and those serving a short sentence. Non-participants experience mainly situational barriers (e.g. having recently arrived in prison), but they also express having preferences for other activities (e.g. working), and being confronted with informational (e.g. not being aware of the possibilities for participation), institutional (e.g. receiving no response to a request to enrol in a course) or dispositional barriers (e.g. not feeling like taking classes). Furthermore, this study investigates which individual, social network and prison-related characteristics are associated with the various categories of barriers. The article concludes with a discussion of the limitations of the study and recommendations for future research.