This study investigates whether students' approach to studying their main honours degree subject differs from how they approach studying mathematics as a service subject. It builds upon work by Crawford, Nicholas, Gordon and Prosser that looked at mathematics students' approaches to studying mathematics and their conceptions of mathematics. Two groups of students from different subject disciplines took part in the study, enabling a comparison of contexts to be made. The results revealed significant differences between the two groups of students, both in terms of their approaches to studying mathematics and their conceptions of mathematics. No difference was found in their approaches to studying their main degree subject.