The Barnes-Jewish Hospital Core Laboratory now offers serologic testing for COVID-19 using the Abbott SARS-CoV-2 IgG serologic assay. The testing, available to patients at BJH and St. Louis Children’s hospitals, allows for the qualitative detection of SARS-CoV-2 IgG, which has been suggested to play a role in COVID-19 diagnosis, identification of patients with presumptive immunity and identification of convalescent plasma donors. However, serologic testing for these purposes has important limitations, which should be carefully considered.