Given the various motivational challenges that students experience when engaging in academic tasks, there is an emerging interest in investigating students' cost perceptions and how to reduce them. However, most of the research has investigated general cost perceptions with a one-time assessment, often divorced from context in which cost is experienced. Centreing the situatedness of students' motivational processes, we conducted an experience sampling study (57 undergraduates; 1,504 responses) to examine the link between general and "in-situ" momentary cost perceptions in students' daily lives, as well as the potential moderating role of motivational regulation. Results showed that certain dimensions of momentary cost perceptions (outside effort cost and emotional cost) were positively associated with their corresponding general cost perceptions. Other dimensions of momentary cost (task effort cost and loss of valued alternatives cost) showed nonsignificant associations, suggesting higher sensitivity to context than others. Moreover, motivational regulation moderated the relationship between general and momentary cost for the majority of the dimensions, suggesting that interventions designed to improve students' motivational regulation may reduce their momentary cost perceptions and increase the positivity of learning experiences.