Introduction: The COVID-19 pandemic resulted in many tertiary institutions switching overnight from taught to online lectures without much preparation. Studies suggest that the sudden change has impacted on students' satisfaction with online learning in differing ways. Yet, little is known about how this change impacted specifically on adult part-time students, which is the focus of this study. Methods: Part-time adult undergraduate students responded to a mixed methods online questionnaire. Close-ended questions were analysed quantitatively in order to determine levels of satisfaction with online learning during COVID-19 as well as its correlates. Open-ended questions were analysed qualitatively in order to explore the perceived benefits and challenges associated with online learning during this period. Results: Levels of satisfaction with online learning were found to be high, especially among students who were female, those who did not have young children, had partners who worked in excess of 40 hours, were able to follow lectures from locations other than the home, and those following non-technical courses. Several benefits of online learning were identified, including time saved on commuting, the ability to study from the comfort of home and the fact that lectures could now be recorded. Challenges included those related to technology, a lack of interaction amongst students and part-time lecturers who struggled with the sudden switch to online learning. Despite this, most students indicated they would like online lectures to continue to various degrees even after it was safe to return to class. Conclusion and implications: Online lectures were generally rated positively by adult part-time students. In view of the benefits and some of the challenges associated with online learning, it is recommended that future academic programmes adopt a blended approach whilst more support is provided to those who find it challenging to follow lectures from home.