BackgroundCOVID-19 vaccine hesitancy seems to be universal across countries and subgroups, and so are its determinants. We studied the willingness and factors associated with the decision to be vaccinated against COVID-19 in healthcare workers (HCW) in a Spanish tertiary hospital. Furthermore, we compared the percentage of willingness to vaccinate against COVID with actual vaccination rates among HCW in our hospital.MethodsFrom December 21, 2020 to January 4, 2021, before initiation of the COVID-19 HCW vaccination campaign at Germans Trias i Pujol University Hospital (HUGTiP), an anonymous self-administered questionnaire was administered to HCW. Univariate and multivariate logistic regression of the association of variables with the outcome “intention to receive the COVID-19 vaccine as soon as possible” was conducted. Vaccination rates were extracted from the hospital information systems.ResultsForty-four percent of HCW included in the study declared a willingness to be vaccinated against COVID-19 as soon as possible. This was associated with male sex [1.66 (95%CI 1.13–2.43); p = 0.009], older age [1.02 (95%CI 1.00–1.03); p = 0.014], belonging to the occupational groups “physician” or “other” [5.76 (95%CI 3.44–9.63) and 2.15 (95%CI 1.25–3.70); p<0.001], respectively, and reporting influenza vaccination during the last three seasons or at least one of the last three seasons [3.84 (95%CI 2.56–5.75) and 2.49 (95%CI 1.71–3.63); p<0.001]. One in ten hospital workers reported they were unwilling to receive COVID-19 vaccination. Actual COVID-19 vaccination uptake among HCW was higher (80.4%) than the percentage of willingness to vaccinate estimated from the questionnaire. Physicians not only had the highest vaccination rate, but also the highest correlation between the reported intention to vaccinate and the final decision to receive COVID-19 vaccination.ConclusionsCOVID-19 vaccination uptake was higher than previously estimated according to the stated intentions of HCW. Doubts and fears must be addressed, particularly in persons less inclined to be vaccinated: females, younger people and those not vaccinated against influenza in recent seasons. The study of barriers and strategies aimed at promoting COVID-19 vaccination must be adapted in relation to occupational groups’ attitudes, understanding their idiosyncrasies with respect to this and other vaccines.