Extensive research on the determinants of people‘s subjective wellbeing has shed light on factors that influence quality of life and that traditional welfare measures tend to neglect. Particularly important among these appear to be the relational, interpersonal aspects of human existence, and both intrinsic and extrinsic benefits of participating in different types of social networks and associative activities. This field of analysis, however, is not devoid of challenges. These include: the wide variety of social proxies adopted in the literature, which has often led to mixed results; and the almost exclusive use of cross-sectional data, which makes it impossible to control for individual unobserved characteristics that could significantly affect both wellbeing levels, and the quality of one’s social and relational context. In this study, we address both of these issues by examining the association between subjective wellbeing, and a rich set of 17 social capital indicators reflecting the following dimensions: personal relationships, social network support, civic engagement, and trust and cooperative norms. Moreover, we use longitudinal data, and control for time-constant sources of heterogeneity among respondents, such as personality traits and predispositions. Our results suggest a consistent relationship between wellbeing and all four dimensions of social capital examined. Furthermore, we find evidence of important gender differences in the way social and relational factors affect overall life satisfaction.