Volunteering to address poor life outcomes often experienced by care leavers is emphasised in UK policy. Although volunteering is credited with the ability to generate social capital, there is limited research on the impact of volunteering on the social capital of care leavers. This article re‐examines data from an evaluation of a volunteering project for care leavers. It explores in what ways young people's participation in the project constitutes social capital. The findings support the importance of regular face‐to‐face contact and co‐production for young people to become creators of their own social capital.