This report is an update of the 2017 European Platform tackling undeclared work report, An evaluation of the scale of undeclared work in the European Union and its structural determinants: Estimates using the Labour Input Method (Williams et al., 2017), that provided estimates of undeclared work in the private sector for 2013. Employing the same methodology, this study provides estimates on the prevalence of undeclared work in the European Union (EU) in 2019.