Online labour platforms enable the trading of services by connecting buyers who need services with providers willing to deliver those services. One crucial element to a platform’s survival and success lies in creating and fostering a thriving community of users – otherwise, the platform is likely to perish. However, we know very little about how such communities can be built. Extant studies have overlooked different stakeholder groups’ roles in community building and how primarily online platforms utilize offline activities. In this paper, we study the community-building efforts of six online labour platforms that have succeeded to thrive longer than an average platform. Beyond the traditional stakeholder roles of providing a marketplace (platform), delivering services (providers) and purchasing services (buyers), we find novel unique and shared roles that foster a well-functioning community. We identify five levers of community building: facilitating trade, encouraging community participation, involving users, empowering providers, and empowering buyers.