The study examined the impact of coursework-only assessment, as made necessary at the onset of the COVID-19 pandemic, adopting a quantitative research approach with 1013 students. The data obtained were analysed using SPSS version 27.0 to obtain descriptive and inferential statistics. The results revealed significant differences between the 2019- and 2020 marks for the same courses. In two of the science courses (T2 and T3), the mean scores for 2019 were significantly higher than the mean scores for 2020. In the mathematics course, the 2020 marks were significantly higher than the marks for 2019. While a normal distribution was assumed for the science courses, the mathematic course showed marks that were skewed to the right. A higher number of distinctions in the F1 course and a significant decline in the mean scores for T1 and T2 implies that there is a need for professional development of lecturers teaching in the online space. It is, therefore, recommended that higher education lecturers need adequate professional development on setting and administering online assessments. The assessment should test adequate lower- and higher-order cognitive skills for sufficient testing of student knowledge during online assessments. Furthermore, a variety of assessment methods and a diversity of tasks may be used to ensure the reliability of the assessment outcomes.