Social capital comprising trust, norms of reciprocity, and networks of civic engagement has increasingly been recognized as a critical, yet often underutilized, resource in efforts to achieve sustainable community development. While economic and environmental capital have long dominated sustainability discourse, the social dimension that binds communities together and enables collective action remains comparatively under-theorized and under-measured in practice. This article synthesizes recent empirical and conceptual literature (2021–2026) to examine how bonding, bridging, and linking social capital influence sustainable outcomes across rural, urban, coastal, and cross-cultural community settings. Using a systematic narrative review method structured around a conceptual social capital framework, the study analyzes evidence drawn from twenty-five peer-reviewed sources spanning Indonesia, Vietnam, Mexico, Ghana, Kazakhstan, Bangladesh, Cambodia, Sri Lanka, and other contexts. Findings indicate that social capital consistently strengthens community participation, collective action, resource governance, and resilience to environmental and economic shocks, although its effects are moderated by institutional trust, digital transformation, and socio-cultural heterogeneity. The novelty of this study lies in its integrative cross-sectoral synthesis linking tourism, agriculture, fisheries, disaster resilience, and religious institutions under a unified social capital lens and in the proposal of an integrated Bonding Bridging–Linking model connecting social capital to the three pillars of sustainability. The article concludes that deliberate investment in social capital infrastructure is essential for durable, community-driven, and equitable sustainable development