Abstract Background Nutri-score is a front of pack labeling system that provides consumers with simplified information of the nutritional quality of food products. It is based on a five color (green to red) or letter (A to E) scheme that grades the quality of the product using an algorithm that takes into account the energy, sugar, saturated fats, salt, fiber, protein content, and percent of fruits and vegetables. In Belgium, Nutri-score was implemented on a voluntary basis in April 2019. This study aims to explore reformulation of products with Nutri-score by comparing their nutrient content and Nutri-score distribution in 2019 and 2021. Methods Product data from one of the major retailers was used in the analysis. Similar products in 2019 and 2021 with matched barcodes were used. Descriptive statistics were computed and statistical analyses such as the signed rank test and the McNemars test were performed to respectively evaluate the changes in the nutrient content and Nutri-score. The tests were conducted at 5% level of significance. Results From the matched sample of 668 products, about 55% had a Nutri-score of A and B in both 2019 and 2021. The proportion of food products with Nutri-Score of A/B and of D/E was not significantly different after two years of Nutri-Score implementation. Results showed a significant decrease in the median energy content of dairy, sauces, and meat products and in the median sugar content of dairy and fruit and vegetable products. There was a significant increase in the median fiber content of the dairy, meat products, and non-alcoholic beverages. For all food groups, the salt content of the products in 2019 and 2021 was not significantly different. Conclusions This two-year interval analysis described the changes in the classification and reformulation of the products with Nutri-score. Favorable changes in the nutrient quality of the product profiles reveals improvement in their reformulation. Key messages • In this analysis, changes has been observed in the nutrient content of food products between 2019 and 2021. • Producers or manufacturers should continue working on commitments to enhance the nutritional quality of the products delivered to consumers.