Educators who administer exams are often met with student desire for extended exam time. Thus far, it has been unclear whether giving students additional exam time serves to improve their exam performance or if this accommodation simply helps students feel more comfortable with taking exams due to inconsistent results. We hoped to design an experiment that would effectively measure the effects of increased exam time on students’ exam performance and test anxiety levels. Because academic performance is negatively correlated with test anxiety, we hypothesized that giving students twice as much to complete an exam would improve their performance, primarily by decreasing their test anxiety levels. We studied two academic quarters of students taking the same undergraduate physiology course. We administered isomorphic exams, with one quarter of students taking the exam with the standard amount of exam time and the other receiving double that amount of time. We compared midterm exam scores for both groups of students, as well as their test anxiety levels before and after the exams as measured via two surveys. We found that increasing exam time did not improve student performance or reduce their test anxiety levels. Increased exam time only reduced students’ reported requests for additional exam time. The implications of our research are that increased exam time allows students to feel more comfortable with taking exams, and increases the likelihood that they will leave an exam feeling satisfied with their performance. Future research should account for demographic differences, as well as differences in academic ability and anxiety disorders, between experimental groups to accurately measure the relationship between increased exam time, performance, and test anxiety.