This article investigates the relationship between four major life events and stopping sport participation in young adulthood. We employ a neo-Weberian theoretical framework related to changes in temporal and social resources to explain how beginning to work, starting to live on one’s own, starting to cohabit or getting married, and the birth of one’s first child affect the risk to stop practising a sport and to end a sport club membership. We used detailed retrospective life-course data from the Dutch SportersMonitor 2010 on 3540 individuals to examine the sport careers and major life events of young adults (aged 18–35). Our event history analyses indicate that the risk to stop practising a sport increases when young adults begin to work, move out to live on their own, and start cohabiting or get married. The risk of ending a sport club membership rises when young adults start to live on their own and when they cohabit or get married. The birth of the first child increases the risks of both stopping a sport and ending club membership for young women, but not for young men.