This study aimed to investigate the effects of supplementary and special examinations on students at Gretsa University in Kiambu County, Kenya, considering their implications for academic performance and holistic development in higher education. The research design was a mixed-method descriptive design that combined quantitative and qualitative data collection and analysis in two distinct stages. The target group for the study included students at Gretsa. The study used stratified random sampling as a sampling technique to select participants from the target group of students. The sample size for the qualitative phase was 100 participants, and the qualitative phase consisted of semi-structured interviews with the participants from the quantitative phase. The results showed that students who utilized supplementary examinations had a higher level of academic performance than those who did not. Students who used supplementary tests were more likely to achieve higher academic performance. The effect of special tests on students with unique academic challenges underscored the importance of accommodating diverse needs within higher education and their interplay with supplementary assessments.