Private entities play a major role in health globally. However, their contribution has not been fully optimized to strengthen delivery of public health services. The COVID-19 pandemic has overwhelmed health systems and precipitated coalitions between public and private sectors to address critical gaps in the response. We conducted a multi-country cross-sectional study in the Democratic Republic of Congo, Nigeria, Senegal and Uganda between November 2020 and March 2021 to document the public and private sector partnerships and engagements to inform current and future responses to public health emergencies. Findings indicate the private sector contributed to the COVID-19 response through engagement in COVID-19 surveillance and testing, management of COVID-19 cases, and health promotion to maintain health access. There is a need to develop regulatory frameworks for sustainable public–private engagements including regulation of pricing, quality assurance and alignment with national plans and priorities during response to epidemics.