Summary Attitudes of healthcare professionals to the importance of hydration for health, wellness and performance were evaluated in six European countries. These included general medical practitioners (n = 600), nurses (n = 300), pharmacists (n = 550), nutritionists (n = 265) and dietitians (n = 265), spread across France, Germany, Greece, Italy, Spain and the UK, who completed computer-aided web or telephone interviews. The interviews assessed attitudes to the importance of hydration, how commonly they assess the hydration status of patients, and knowledge about recommended water intakes, sources of water for consumption and contribution from different beverages. All responders considered hydration an important issue and there was little difference in opinion between different healthcare providers. Responders in Mediterranean countries (particularly Italy and Spain, but also Greece to some extent) rated hydration more importantly than those in Germany and the UK (P < 0.001) and this was reflected in the higher frequency with which they reported that they assess the hydration status of patients (P < 0.001) and provide advice on the subject (P < 0.001). It was also demonstrated by a greater percentage of responders citing the necessity of optimal hydration for physical performance in these countries, compared with Germany and those in the UK and France (P < 0.001). Whether this was caused by climatic or cultural differences was not addressed by the study. The contribution of an appropriate hydration status to mental health was relatively poorly recognised, with less than 50% of responders in all countries citing this as a benefit and less than 30% of those in France and Italy citing it as a reason to provide advice. Healthcare professionals were reasonably knowledgeable about European Food Safety Authority adequate intakes for water for men and women but overestimated the contribution from food and underestimated that from beverages. The data highlight opportunities for education and improved clinical practice, especially in respect to the effects of hydration status on mental wellbeing and performance and the contribution of foods and beverages to total water intake.