Collaborative two-stage exams provide an effective mechanism to incorporate group work into summative course assessments. We implemented these exams in an upper-level biology laboratory course over two terms, one with online exams and one with in-person exams. We compared student exam performance and perceptions of two-stage exams and group work across terms and demographic groups. Quantitative analyses revealed that across three exams per term, students in groups outperformed students who took the exams individually, and on average the group exam benefited all students, in particular students from groups recognized as persons historically excluded from science because of their ethnicity or race (PEERs). Student responses to both closed and open-ended questions indicated overall positive perceptions of both two-stage exams and group work. We found no significant differences in student perceptions based on PEER student status, gender, or the number of exams helped by group exams, but we found differences related to term and group exam approaches. These findings build upon the literature supporting student learning and perceptions from two-stage exams and provide novel insights for a role of group work in decreasing inequities in course assessments.