The current COVID-19 pandemic is marked by strong uncertainties that have had significant ramifications for banking systems around the world. As a result, bank lending has declined sharply. This raises a central question: Would vaccination against COVID-19 encourage a return of bank loans? To answer this question, we first consider an original epidemiological model to study the impact of vaccination on banks’ loan supply. The impact of vaccination and infection force on endemic steady state is computed, and then we consider how these two characteristics of COVID-19 epidemics impact banks’ loan supply. Second, we empirically test this relationship using data from 3772 US banks over the period 2020Q1-2021Q2. Our results show that bank lending was lower at the onset of the health crisis. We also find that the growth rate of loans is higher during the period with the vaccine than during the period without the vaccine. This result therefore highlights the importance of COVID-19 vaccination in boosting bank’s lending. In addition, we find that the effects of vaccination on lending supply depend on bank-specific characteristics. Specifically, our results suggest that banks that were stronger (either higher margins or more capitalized or larger) before the onset of the vaccination, have higher growth rate of lending than other banks.