AbstractVolunteering provides unique benefits to organisations, recipients, and potentially the volunteers themselves. This umbrella review examined the benefits of volunteering and their potential moderators. Eleven databases were searched for systematic reviews on the social, mental, physical, or general health benefits of volunteering, published up to July 2022. AMSTAR 2 was used to assess quality and overlap of included primary studies was calculated. Twenty-eight reviews were included; participants were mainly older adults based in the USA. Although overlap between reviews was low, quality was generally poor. Benefits were found in all three domains, with reduced mortality and increased functioning exerting the largest effects. Older age, reflection, religious volunteering, and altruistic motivations increased benefits most consistently. Referral of social prescribing clients to volunteering is recommended. Limitations include the need to align results to research conducted after the COVID-19 pandemic. (PROSPERO registration number: CRD42022349703).