The main aim of the paper is to investigate student excuses in emails written by Hungarian university students to their instructor, as well as to examine students’ perceptions of the acceptability of these excuses. First, the analysis of a corpus of student emails (n = 74) shows that students make excuses most frequently because they would like to request the extension of deadlines for their assignments.What is more, the most common excuses students send to the instructor in email are related to technical problems (computer, internet) and to their health (illnesses). Furthermore, data provided by Hungarian university students (n = 83) on the acceptability of excuses indicate that students find family-, health- or technology-related excuses acceptable, whereas they believe that not understanding the assignment, being forgetful, and considering the task boring or unchallenging are rather inadequate excuses to make when missing a deadline. Finally, the analysis of the interview data provides an insight into some of the factors, i.e. control, timing, and proof, that influence the perceptions of participants (n = 53) regarding excuses in student emails.