Prior studies suggest associations between course performance and well-being and self-efficacy, although what comes first in this effect remains unclear. This study contributes to the research on noncognitive aspects of learning of first-year students, and examines the bidirectional relation between, on the one hand, students' well-being and self-efficacy, and on the other hand, their course performance in an accounting course. The study investigates first-year undergraduate students and their performance in an accounting course, measured as the grade and ensuing pass/fail mark. Longitudinal survey data were collected at three data collection moments during two consecutive semesters. The results lead to three main findings. First, well-being a few weeks before the examination moment affects course performance (grade) in accounting, while self-efficacy does not. Second, students who passed the course had higher well-being and self-efficacy in the next semester than those who failed. Third, students who passed, reported a higher increase in well-being and self-efficacy after the examination moment, than those who failed. Analyses controlled for students' age, gender, and high school performance. The empirical results provide valuable longitudinal insights into the important role of well-being and self-efficacy in relation to course performance, and vice versa. Implications for theory and practice are provided.