Over a half of Angola’s urban population live in slums where they face challenges including overcrowding, insecure tenure, and a lack of basic services. In the context of the COVID-19 pandemic, this demographic is left particularly vulnerable. However, insufficient data about the living conditions and real needs of these settlements make designing appropriate policies difficult. It is for this reason that the NGO Development Workshop (DW) with the support of UN-Habitat Participatory Slum Upgrading Programme (PSUP) conducted a community-based research study, wanting to explore the impacts of the pandemic on communities in Angola’s informal settlements (musseques) and aiming to enrich the scholarship on informal urban settlements in the Global South in the times of COVID-19. Telephonic interviews were conducted with over 1600 slum dwellers in the country’s 18 provinces, although the study sample was weighted toward major urban centers where COVID-19 transmission is highest. The impact of the pandemic on the family’ economy was assessed, as well as difficulties with securing goods and services. The study examined people’s perceptions of the government COVID-19 mitigation strategies and the degree to which households received emergency support during the pandemic (from the government and other sources). While unemployment rates did not increase significantly among slum dwellers (likely because those already engaged in the informal economy continued to work despite declining returns), overall income decreased and expenses increased sharply, leaving families more vulnerable and with little to no extra help. The article closes with an outline of a strategy for participatory slum upgrading in the context of the pandemic, proposing a set of community-based initiatives that could lead to increased resilience in face of the current public health crisis, and to sustainable upgrading practices in the long run.