BACKGROUND: When the coronavirus pandemic caused widespread school and business closures in March 2020, blood drives were canceled and the supply of blood decreased suddenly in the United States (US). In response, hospital-based transfusion medicine physicians instituted policies to conserve blood and decrease blood product usage. These efforts were aided by the US Surgeon General recommendation to cancel all elective procedures. Nevertheless, the duration, severity, and impact of the pandemic on the national blood supply was uncertain. Hospitals with in-house donor programs had the opportunity not only to control demand, but also increase supply. STUDY DESIGN AND METHODS: A hospital-based blood donor center was rapidly mobilized to increase the supply of in-house collected blood, in order to counteract a sudden but potentially long-term depletion of the national blood supply during a pandemic. RESULTS: Collections increased approximately five-fold above baseline for whole blood units, while apheresis platelet units were maintained at the historical average for the blood donor center. Cancellation of elective procedures showed a modest, but not yet statistically significant decrease in average blood product usage per day, nevertheless the in-house collection rate was sufficient to meet demand. CONCLUSION: A hospital-based blood donor center can quickly increase collection volumes and capacity in the face of a national emergency or pandemic. The desire to collect units should be balanced with safety concerns, need for sustainability, and blood product demand.