The European Health Literacy Survey (HLS-EU) is the first comparative survey on health literacy across eight European countries: Austria, Bulgaria, Germany, Greece, Ireland, the Netherlands, Poland, and Spain. The survey aimed to assess health literacy levels and identify vulnerable groups with limited health literacy. The HLS-EU-Q, a 47-item questionnaire, was developed to measure health literacy, with results indicating that at least 1 in 10 respondents had insufficient health literacy, and nearly half had limited health literacy. The distribution of health literacy levels varied significantly across countries, with Bulgaria having the highest proportion of limited health literacy (over 60%) and the Netherlands the lowest (around 20%). Vulnerable groups, such as those with poor health status, low socio-economic status, lower education, and older age, had higher proportions of limited health literacy. A social gradient was identified, with financial deprivation, social status, education, and age being significant predictors of limited health literacy. The survey highlights the importance of addressing health literacy deficits in public health policies and practices across Europe. The findings suggest that health literacy is a key priority on the EU agenda, and that public health strategies should consider the social determinants of health and health inequalities. The HLS-EU survey provides valuable insights into the variation in health literacy levels across the EU and supports the development of targeted interventions to improve health literacy and health equity.The European Health Literacy Survey (HLS-EU) is the first comparative survey on health literacy across eight European countries: Austria, Bulgaria, Germany, Greece, Ireland, the Netherlands, Poland, and Spain. The survey aimed to assess health literacy levels and identify vulnerable groups with limited health literacy. The HLS-EU-Q, a 47-item questionnaire, was developed to measure health literacy, with results indicating that at least 1 in 10 respondents had insufficient health literacy, and nearly half had limited health literacy. The distribution of health literacy levels varied significantly across countries, with Bulgaria having the highest proportion of limited health literacy (over 60%) and the Netherlands the lowest (around 20%). Vulnerable groups, such as those with poor health status, low socio-economic status, lower education, and older age, had higher proportions of limited health literacy. A social gradient was identified, with financial deprivation, social status, education, and age being significant predictors of limited health literacy. The survey highlights the importance of addressing health literacy deficits in public health policies and practices across Europe. The findings suggest that health literacy is a key priority on the EU agenda, and that public health strategies should consider the social determinants of health and health inequalities. The HLS-EU survey provides valuable insights into the variation in health literacy levels across the EU and supports the development of targeted interventions to improve health literacy and health equity.