question: We have established a split nano-luciferase complementation assay to rapidly screen for inhibitors that interfere with binding of the receptor binding domain (RBD) of the SARS-CoV-2 Spike glycoprotein with its target receptor, Angiotensin Converting Enzyme 2 (ACE2). Following a screen of 1,200 FDA-approved compounds, we identified Bifonazole, an imidazole-based antifungal, as a competitive inhibitor of RBD-ACE2 binding. Mechanistically, Bifonazole binds ACE2 around residue K353, which consequently prevents association with RBD, thereby impacting entry and replication of Spike-pseudotyped viruses as well as native SARS-CoV-2 and its variants of concern (VOC). Intranasal administration of Bifonazole reduces lethality in K18-ACE2 mice challenged with VSV-Spike by 40%, with a similar benefit after live SARS-CoV-2 challenge. Overall, our screen has identified an antiviral that is effective against SARS-CoV-2 and VOCs such as Omicron that employ the same receptor to infect cells, and therefore has high potential to be repurposed to control, treat, or prevent COVID-19.