This folder contains three datasets (Microsoft Excel), two participant information sheets (PIS, English and Dutch), and two consent forms (English and Dutch) used in "Estimating loss in capability well-being in the first year of the COVID-19 pandemic: a cross-sectional study of the general adult population in the UK, Australia and the Netherlands" published in the European Journal of Health Economics doi: 10.1007/s10198-022-01498-y. Each of the three Microsoft Excel files contains three sheets with the data, labels and variables reported for the United Kingdom (UK), Australia (AUS) and the Netherlands (NL), respectively. Data were collected between 26 January and 2 March 2021. Users will require Microsoft Excel to access this data and Acrobat to read the PIS and consent forms.