Community-based peer volunteer interventions are increasingly used with people who are asylum seekers and refugees accessing health services. There is a dearth of evidence evaluating the benefits of volunteering for asylum seeking or refugee volunteers. Volunteers may have poor mental health and feel socially isolated due to their experiences as refugees and asylum seekers and may struggle or be unable to obtain paid employment. Volunteering in other contexts has been found to be beneficial to the health and well-being of the volunteer. This paper reports on an aspect of a wider study evaluating the community-based Health Access for Refugees Project, with the aim of exploring the impact of volunteering on the health and well-being of the peer (asylum seeker or refugee) volunteer. In 2020, we conducted qualitative semistructured interviews by phone with 15 volunteers who were asylum seekers or refugees. The interviews were audio recorded, data were transcribed verbatim and the data set was thematically analysed. We found that the positive relationships which developed and the training received through volunteering boosted volunteers' mental well-being. They felt motivated and confident in helping others, felt a sense of belonging and this reduced their social isolation. They also believed they benefited personally, helping their access to health services, and preparing them for future education, training or a career. In light of the beneficial nature of volunteering identified in this study, establishing more volunteering opportunities for this population and other marginalised groups with poor mental health is recommended. However, more research is needed to assess both the long-term impact of the role in terms of the peer volunteer's health and well-being, and the societal benefit of people moving on, integrating and contributing to society.