Background Religious communities have been identified as an important source of social support for children. Although church children's ministries (i.e., church programs where children receive religious education separate from their parents) have been suggested as a potential avenue for the transmission of social support, the specific children's ministry practices that promote social support have not been established empirically. Purpose The purpose of the present study was to determine whether contemplative-reflective practices, structured playtime, and unstructured playtime predict between-church differences in children's church-based social support (i.e., received support, perceived support from peers, perceived support from adults) controlling for children's individual characteristics and children's ministry size. Methods Using a multilevel approach, we analyzed self-report survey data from 43 children's ministers and 1,090 children from 43 Church of the Nazarene congregations in the United States. Results Results showed that children's supportive experiences were largely predicted by their individual characteristics (e.g., family religiosity, agreeableness). However, contemplative-reflective practices had a medium positive effect on received support and perceived support from peers and adults. Unstructured playtime had a medium positive effect on received support only. Structured playtime was unrelated to all three outcomes. Conclusions and Implications These findings suggest that, although some children are naturally predisposed to thrive socially at church, children's ministry practices appear to have a significant and substantive impact on children's church-based social support. The results shed light on the conditions that create and sustain church-based social support. Churches wishing to make children feel part of a supportive community should consider incorporating contemplative-reflective practices into their children's worship service (e.g., mindful prayer and reflective experiences, meaningful choices, leadership opportunities for children, safe and intimate opportunities to share and receive prayer, and liturgical traditions), as well as regular space for unstructured playtime wherein children can exercise autonomy, demonstrate their unique talents and abilities, and engage in informal conversations with peers and adults about their life experiences, feelings, and personal problems.