Globally, healthcare systems are facing the enormous challenge of the COVID-19 pandemic. Ethiopia is currently implementing different preventive measures to interrupt the transmission of SARS-CoV-2. The early effect of these preventive measures on essential healthcare service delivery is unknown. In this study, we looked at the number of essential healthcare visits over 8 weeks, 4 weeks before and 4 weeks after the implementation of preventive measures. During the implementation of these measures, patient flow decreased in all elements of essential healthcare service. The decline was dramatic for family planning (98%), emergency surgery (77%), and follow-up of chronic surgical conditions (70%). An understanding of the reasons behind the decrease in patient flow is urgently needed to design ways of sustaining essential care.