Background: Bamlanivimab (LY-CoV555; BAM), a monoclonal antibody therapy for mild-to-moderate Severe Acute Respiratory Syndrome Coronavirus 2(SARS-CoV-2), has been granted an Emergency Use Authorization (EUA) in the United States. Our goal was to determine if BAM prevented emergency department (ED) visits, hospitalizations for SARS-CoV-2, or death within 60 days of a positive SARS-CoV-2 viral test. Setting and Participants: Patients (N=2,107) eligible to receive BAM from November 1 to December 31, 2020, were identified. Eligible patients had mild-to-moderate SARS-CoV-2 disease, a positive SARS-CoV-2 test, and risk factor(s) for progression to severe SARS-CoV-2 infection. All patients were reviewed for subsequent ED visits, subsequent hospitalization, and death. Intervention: A total of 144 of 2,107 patients with mild-to-moderate SARS-CoV-2 received BAM. Patient propensity matching was performed for BAM administration to get two discrete groups of patients; those who received BAM (n=117) and those who did not (n=117). Continuous variables are presented as median and interquartile range (IQR). Discrete variables are presented as counts and proportions. Results: Patients (n=234) were matched, 117 in each group. Median (IQR) age was 72 (65-80) years.Forty-seven percent of patients were male. Twenty-one patients who received BAM were subsequently seen in the ED compared to 34 untreated patients (18.0% vs. 29.1%; P = 0.045).Fourteen BAM-treated patients were subsequently hospitalized post-BAM infusion compared to 27 untreated patients (12.0% vs. 23.1%; P = 0.025). Finally, there were no mortalities in the BAM group, however, eleven patients in the untreated group died (0.0% vs. 9.4%; P < 0.001). The number needed to treat (NNT) is 11 patients to prevent one mortality event.Conclusions: BAM infusion for mild-to-moderate SARS-CoV-2 infection in outpatients significantly prevented subsequent ED visits, hospitalizations, and death from SARS-CoV-2.