This study investigated differences in vocabulary knowledge as a potential explanation for perceived differences between placed and promoted students in a university EAP reading course. Students in an advanced reading course (N=59) were tested on their vocabulary knowledge using the Vocabulary Levels Test Form B [Nation, I. S. P. (2001). "Learning vocabulary in another language." Cambridge: Cambridge University Press] at the beginning of the academic semester. Additionally, the promoted students' (n=29) vocabulary scores were compared to their own scores from the beginning of the intermediate course one semester earlier. Analysis of the data shows that students placed directly into the advanced reading course upon entry to the university have statistically significantly greater vocabulary knowledge than students promoted into the course after one semester of study in the EAP program. This difference was observed for both general as well as academic vocabulary knowledge. Moreover, promoted students' vocabulary scores showed no significant increase over their initial scores as intermediate students for either general or academic vocabulary knowledge despite the fact that they had taken one or more university content courses. Potential reasons for these results as well as curricular implications are discussed. (Contains 2 figures and 8 tables.)