AbstractThe financial viability of many not‐for‐profit organisations is linked to community fundraising by volunteers. This study explored predictors of volunteer retention and fundraising performance in relay for life (RFL), an international volunteer community‐based cancer fundraising event. A self‐report survey completed by 1298 RFL volunteers (24% response) assessed: satisfaction with volunteering; organisational commitment; psychological sense of connection; motives; social norms; capacity to volunteer as in perceived behavioural control and barriers to volunteering; satisfaction with community; behavioural intention. Primary outcomes were return participation in RFL and funds raised. Returning volunteers reported higher perceived behavioural control and satisfaction with community. Indirect effects through age‐moderated intention‐to‐return were higher satisfaction with volunteering; organisational commitment; psychological sense of connection; capacity to volunteer. Funds raised were higher in teams with volunteers who were older, strongly committed to the organisation and motivate to fight cancer; with low interest in social/entertainment. Strategies to nurture the volunteer‐organisation relationship and enhance volunteer capabilities may be most crucial for event success and long‐term viability.