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• The Roche Elecsys anti-SARS-CoV-2 and the Abbott SARS-CoV-2 IgG assay both had 100% specificity. • Overall sensitivity of the Roche assay was 92.1% at ≥14 days and 94.8% at ≥21 days, and the overall sensitivity of the Abbott assay was 94.4% at ≥14 days and 98.2% at ≥21 days. • Low rates of seroconversion seen in the immunocompromised (95.2% vs. 81.0% sensitivity at ≥21 days). • Sensitivity in the immunocompromised was numerically higher with the Abbott assay. • After excluding samples from immunocompromised patients sensitivity of both assays appeared excellent (100% for both assays at ≥21 days. • Short-term antibody waning was demonstrated with both assays. • Seroreversion was seen with the Roche assay. Introduction: During the COVID-19 pandemic, widespread introduction of SARS-CoV-2 antibody testing was introduced without a full understanding of the assays performance or the antibody kinetics following infection with SARS-CoV-2. Methods: We performed an evaluation of 2 anti-SARS-CoV-2 antibody assays with a more detailed look into the effect of immune status on antibody sensitivity. Results: Both assays demonstrated 100% specificity. The overall sensitivity of the Roche was 92.1% at ≥14 days and 94.8% at ≥21 days, and the overall sensitivity of the Abbott was 94.4% at ≥14 days and 98.2% at ≥21 days. 7/41 (17%) of patients included in this cohort were immunocompromised. Seroconversion was seen less commonly in the immunocompromised (4/7 [57.1%] seroconverted) and after excluding these patients 100% sensitivity was seen in both assays at ≥21 days. Discussion: Performance of both assays in the immunocompetent appeared excellent after 21 days postsymptom onset. Both assays are highly specific. [ABSTRACT FROM AUTHOR]