Senior population provides significant amount of volunteer work in communities across America. Using data from the Arizona Health Survey 2010, this study examines the impact of social context on senior volunteering. The results show that seniors who have more friends to rely on, who often hang out with others, help friends and neighbors, and participate in social clubs or religious and other organizations are more likely to volunteer. Education and self reported physical health also increase their chance of volunteering. Additionally, African American seniors are more likely to report volunteering than their Hispanic counterparts. The findings suggest the importance of social context in encouraging senior volunteering and imply the significance of network-based volunteer recruitment among seniors.