Regular voluntary engagement is a basic resource for sports clubs that may also promote social cohesion and active citizenship. The satisfaction of volunteers is an imperative factor in this engagement, and the purpose of this article is to explore individual and organizational determinants of volunteer satisfaction in sports clubs. Theoretically, our study builds on the actor-theory concepts where volunteer satisfaction depends on subjective evaluations of expectations and experiences in a sports club (‘logic of situation’), so that positive evaluations lead to higher satisfaction and, hopefully, retention of volunteers. This research uses a sample of 8131 volunteers from 642 sports clubs in 10 European countries, and is the first analysis to combine determinants at the level of the club and the volunteer (multilevel). Results show that the most important determinants of satisfaction are the conditions of volunteering (recognition, support, leadership and material incentives) and the workload of volunteers. Surprisingly, club characteristics, size or having paid staff are not significant determinants of volunteer satisfaction. The results of this analysis can assist more effective volunteer management in sports clubs that are facing challenges of individualization and professionalization.