Education is associated with a wide range of positive outcomes such as higher wages and employability, but also with increased well-being or volunteering. While previous research focused mainly on returns on formal education in schools or universities, there has been a notable shift in recent years towards the analysis of returns on adult learning. While research has established theory-driven empirical evidence concerning labour market-related outcomes, it fails to identify and coherently explain non-monetary outcomes. The authors of this article review 13 empirical studies on different forms of civic participation as a return on engagement in adult learning. Individuals' civic participation is one precondition to social cohesion and functioning citizenship at a societal level and thus a factor of high political and societal relevance. All the studies reviewed in this article suggest a positive association between adult learning and civic engagement. To what extent this association is causal, however, remains an open question. The authors argue that any efforts to identify such causality must begin with a number of theoretical assumptions about the mechanisms through which learning may influence civic participation. By linking the theoretical ideas of the studies reviewed with the literature on volunteering, the authors suggest a new theoretical framework, which may guide further research.