This study investigated the association between students' perceptions of digital accessibility and competence, self-efficacy for self-directed learning (SDL) and their self-rated final grades in the virtual laboratory course during the COVID-19 outbreak. Data were collected from 217 engineering students enrolled in four virtual undergraduate laboratory courses at a mid-sized public 4-year university in the United States. Findings showed that students' digital application usage, information-seeking skills and self-efficacy for SDL were significantly associated with virtual laboratory performance. Thus, universities should provide students with opportunities for improving their digital competencies (e.g., using digital applications, searching for information related to academic work) before attending virtual laboratory courses. Promoting students' self-efficacy for SDL in virtual laboratory environments optimises students' performance potential and goal achievement in these virtual learning settings.