Front-of-pack labelling (FOPL) systems, such as the Nutri-Score, play a crucial role in promoting healthy diets and raising consumer awareness. Our study aimed to gather the opinions of Polish experts on the Nutri-Score and its relation to an ideal information system. We conducted a Poland-wide expert opinion study using a cross-sectional design survey with 75 participants, who had an average of 18 ± 13 years of experience and were mainly employed at medical and agricultural universities. The data were collected with the CAWI method. The results showed that the most important features of an FOPL system were clarity, simplicity, consistency with healthy eating recommendations, and the ability to objectively compare products within the same group. While more than half of the respondents believed that the Nutri-Score provides an overall assessment of a product’s nutritional value and facilitates quick purchasing decisions, it falls short in helping consumers compose a balanced diet and cannot be applied to all product groups. The experts also expressed concerns about the system’s ability to account for a product’s degree of processing, full nutritional value and carbon footprint. In conclusion, Poland’s current labelling system needs expansion, but the Nutri-Score requires significant and detailed changes and validation against national guidelines and expert expectations before implementation.