PURPOSE: Contemporary food systems pose challenges for both human and planetary health. This study aimed to assess and compare adherence to the Planetary Health Diet (PHD) in nine European countries. METHODS: Nationally representative dietary surveys (post-2013) from Estonia, Finland, France, Hungary, the Netherlands, Portugal, Spain, Switzerland, and the United Kingdom, with ≥ 2 non-consecutive 24-hour recalls, were used (n = 16,083 adults). Adherence to the PHD was assessed at two levels: (1) food group compliance, evaluated as the alignment with PHD target values and recommended ranges; (2) overall adherence, captured by three valid dietary indices. Multivariate regression analyses were conducted to identify associations with demographic factors. RESULTS: Dietary patterns across Europe were characterised by insufficient intake of plant-based foods (whole grains, legumes, nuts, vegetables, and unsaturated oils) relative to PHD targets, alongside excessive consumption of foods to limit (red meat, saturated fats, and added sugars). Spain, Portugal, and the Netherlands showed comparatively better alignment with the PHD, whereas Hungary, the United Kingdom, and Estonia had the lowest scores. Red meat, particularly pork, and added sugars were the primary contributors to low scores across PHD indices. Being female, older, and having a higher level of education were positively associated with PHD adherence. CONCLUSION: European diets show systematic deviations from the PHD. Targeted and multilevel policies are needed to promote healthy and sustainable diets. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s00394-026-03929-5.