Across sub-Saharan Africa, stigma levels have been decreasing but not enough to achieve the 95–95–95 HIV targets by 2030. Current global HIV frameworks have identified stigma reduction, context specific interventions, and community mobilization as critical to enabling more effective uptake of HIV services. We conducted a retrospective analysis of longitudinal qualitative and quantitative data collected in 21 urban communities in Zambia and South Africa involved in the HPTN071 (PopART) trial between 2014 and 2019. We illustrate in four communities how three sociostructural features of communities intersected with stigma at the community level: intergroup tensions, the community responses to sociodemographic change, and the local history of HIV initiatives. Tension between different social groups often functioned as a catalyst for stigmatizing attitudes. Sociodemographic change at community level took the form of rapid housing development, population expansion, and outsiders moving in. The ability and willingness of a community to respond to this sociodemographic change and antistigma initiatives influenced HIV stigma. Our findings illustrate patterns in how community-level dynamics influence the trajectory of stigma and point toward a key strategy for accelerating reductions in stigma across sub-Saharan Africa. Community-led approaches, which take local context and dynamics into account, are critical to address the societal enablers of HIV, including eliminating stigma and discrimination. Further, stigma-reduction activities should build on community HIV history, be sensitive to involuntary disclosure, speak to “othering” linked to intergroup tensions, and be a consistent component of HIV programming, given the protection such programming provides against stigma and discrimination.