Here we describe the timeline of events around the first COVID-19 case imported to Finland, and summarise the clinical, molecular and serological data. Successful SARS-CoV-2/Finland/1/2020 isolation enabled us to use the cytopathic effect (CPE)-based microneutralisation (MN) assay to detect SARS-CoV-2-specific neutralising antibody levels. Diagnostic serum samples of the case and three close contacts were analysed and compared with serum samples from the Finnish population collected in 2019.