Background: Novice student nurses encounter challenges when making the transition to clinical learning because of the complex and unpredictable nature of clinical settings. A selected campus initiated a peer-mentoring programme based on research findings, which revealed that student nurses were inadequately mentored in clinical settings because of mentors experiencing work overload, time and resource constraints, staff shortage and patient-care demands.Aim: The aim of this study was to describe the perceptions of student nurses regarding barriers and benefits of a peer-mentorship programme in a clinical setting.Setting: The study was conducted in a clinical setting in KwaZulu-Natal.Methods: A quantitative, descriptive design was used, whereby data were collected through questionnaires. A total of 56 mentors (third- and fourth-year nursing diploma student nurses) and 94 mentees (first- and second-year nursing diploma students) participated in the study.Results: The mentors highlighted insufficient practice opportunities because of the short duration of the placement, time and resource constraints, and the simultaneous mentoring of too many students as barriers, while the mentees highlighted the reluctance of mentors to fulfil their roles and lack of dedication and unfriendliness as barriers to effective mentorship. The benefits of being a mentor were self-achievement, enhancement of skills and acquiring of positive work ethics, while the major mentee benefits included experiencing less anxiety, adapting to the clinical environment easily and being less intimidated in the clinical setting.Conclusions: This study revealed that both mentors and mentees perceived peer-mentoring programmes as important to their clinical growth. However, these programmes require formative evaluations to address negative perceptions of student mentees and mentors and to identify challenges faced by them.