The UK's largest supermarkets—Tesco, Sainsbury's, Asda, and Morrisons—are facing new legal requirements under the updated Price Marking Order (PMO), which mandates clear and unambiguous selling and unit prices for all goods sold in-store and online.
What the Price Marking Order Requires
The PMO, originally enacted in 2004, has been revised to strengthen transparency. Retailers must now display unit prices more prominently, especially for products on promotion or with loyalty pricing. The amendments update definitions and expand obligations to ensure price information is sufficiently transparent for consumers to make informed comparisons between products.
Which? Campaign and CMA Review
Consumer group Which? used its research to highlight shortcomings in supermarket unit pricing. The Competition and Markets Authority (CMA) subsequently launched a review, which aligned with Which?'s findings. The Labour government consulted on reforming pricing legislation as part of a wider transparency consultation, leading to proposals to update the PMO.
Legislative Changes and Implementation
Which? worked to influence the draft legislation, and the revised PMO passed into law in 2024. The government has since made further revisions to simplify unit pricing for consumers. Key changes include clearer requirements on legibility and mandatory inclusion of unit pricing for promotional and loyalty-priced items.
Monitoring and Future Steps
Which? will monitor the implementation of the new provisions to ensure the revised legislation makes a practical difference. The group also plans to increase awareness of unit pricing as a tool for comparing prices and getting the best value.
Reactions from Stakeholders
Sue Davies MBE, Head of Consumer Rights and Food Policy at Which?, said: "Unit pricing in supermarkets is something that can too often go unnoticed. But it is a brilliant tool to help people save money by comparing like-for-like across different brands or different sized products when it is clear and easy to use. We’re delighted that the SMK Foundation has recognised the value of this campaign and Which?’s success in making the case for pricing that works better for consumers."
Herrington Carmichael, a law firm, added: "The Price Marking Order 2004 is designed to ensure consumers can make informed purchasing decisions by requiring clear and transparent price information. This is particularly important where products are sold in different sizes, or where promotions, discounts, and loyalty pricing apply. The purpose behind the recent Price Marking Order reforms is to strengthen this transparency. The changes expand the scope of unit pricing to more product categories, clarify how selling and unit prices should be displayed where multiple prices apply, and introduce updated definitions, including a new requirement to display deposits separately."
