This study aimed to evaluate the performance of SARS-CoV-2 point-of-care and laboratory serology assays and the seroprevalence of SARS-CoV-2 infection among health-care workers with high exposure to COVID-19 in the UK. Phase 1 of the study compared the performance of two point-of-care lateral flow serological assays (Onsite CTK Biotech IgG/IgM Rapid Test, Poway, CA, USA and Encode IgM/IgG One Step Rapid Test Device, Zhuhai, China) to a laboratory immunoassay (EDI IgG ELISA kit, San Diego, CA, USA) using 300 samples from health-care workers and 100 pre-COVID-19 negative control samples. Phase 2 of the study involved serosurveillance of 1299 symptomatic health-care workers and 450 asymptomatic health-care workers. In phase 1, the Encode assay demonstrated increased sensitivity [93.4% (95% CI 87.8% - 96.9%)] and specificity [99.0% (94.6% - 100.0%)] compared to the Onsite assay [sensitivity 88.2% (81.6% - 93.1%)], [specificity 94.0% (87.4% - 97.8%)]. In phase 2, seroprevalence was estimated to be 10.6% (95% CI 7.6% - 13.6%) among asymptomatic health-care workers and 44.7% (42.0% - 47.4%) in symptomatic healthcare workers. The authors caution against the interpretation of negative results across all assays.