Objectives. Although there are numerous studies on the role of social connections in early working life, research that examines how social connectedness matters in the later stages of a career is scarce. The present study analyzes to what extent social connectedness affects the timing of the transition from work to retirement. Methods. We draw on data from the German Socioeconomic Panel Study (GSOEP) from the years 1985–2009 (N = 10,225), and we apply techniques of event history analysis. Social connectedness includes social gatherings with friends, relatives, and neighbors (informal participation) as well as engagement in voluntary and civic associations and local politics (formal participation). Results. The findings demonstrate that social connectedness matters for the transition from work to retirement, but its impact depends on the type of participation. Whereas informal participation results in earlier retirement, formal participation delays labor force withdrawal. Discussion. The findings suggest a trade-off between informal participation and work in later life, which leads people with frequent social contacts to opt for early retirement. By contrast, the fact that formal participation is associated with postponed retirement points to employment benefits of volunteering and civic engagement among older workers.