This paper investigates how social networks in poor developing settings are affected if people migrate. Using a unique household survey from two southern regions in Mozambique, we test the role of labor mobility in shaping participation in groups and inter-household cooperation by migrant-sending households in village economies at origin. We find that households with successful migrants (i.e. those receiving either remittances or return migration) engage more in community-based social networks. Our findings are robust to alternative definitions of social interaction and to endogeneity concerns suggesting that stable migration ties and higher income stability through remittances may decrease participation constraints and increase household commitment in cooperative arrangements in migrant-sending communities.