Previous studies have suggested that a student's personal epistemological beliefs can be a predictor of their academic performance. The current research aimed to extend this work by exploring whether the disciplinary epistemological beliefs presented to students in their classes and assessments might mediate the relationship between students' personal epistemological beliefs and performance. A comparison of a student's personal epistemological beliefs with the epistemological beliefs presented in their classes and assignments was carried out, establishing the level of "epistemic match" between student and discipline. It was expected that epistemic match would be a predictor of a student's performance. A total of 362 first year students from eight subject disciplines at a UK university completed a questionnaire measure of personal epistemological beliefs. A total of 38 staff from the same disciplines also completed a questionnaire which was adapted from the original student version to represent a measure of the presented epistemological beliefs in their discipline. The results showed a significant relationship between performance and levels of epistemic match. Closer epistemic match was associated with higher performance. The conclusion is that epistemic match is a reliable predictor of students' performance in their first year.