This is a replication dataset for the manuscript titled: "Temporal trends of SARS-CoV-2 seroprevalence in transfusion blood donors during the first wave of the COVID-19 epidemic in Kenya". These data contain anonymised residual donor serum samples used for screening of transfusion transmissible infections were collected at the KNBTS regional centres in 4 sites (Mombasa, Nairobi, Eldoret and Kisumu) which has been used to compute standardised prevalence by age, sex and region using KNBS population as the standard population.