In current food environments, energy-dense, nutrient-poor foods are readily available, heavily marketed and relatively cheap. Consumers are challenged to make healthy and affordable food-related decisions that are consistent with a healthy diet. Affordability of food is a key determinant of the food environment and changes in price influence consumer demand for many foods and beverages. Fiscal measures, including both taxation and subsidies have long been recognized as a viable policy option to promote healthy diets. Despite some progress in implementing fiscal measures, governments continue to face challenges in their attempts to develop such measures. This WHO guideline provides Member States with recommendations and implementation considerations on fiscal policies to promote healthy diets, including on food and beverage taxation, and on food subsidies that have the primary intention to change consumer behaviour by lowering prices of targeted products at retail level. Guidelines on other policies to improve the food environment are currently under development.