Shoppers have been urged to keep an eye out for hidden codes on supermarket shelves that reveal when promotions end. Tesco, Sainsbury's and Waitrose all use these secret systems, allowing savvy customers to purchase items before they return to full price.
At Tesco, the discount end date is written backwards on the shelf label. For example, the code '250121' means the deal ends on 21 January 2025. The first two digits indicate the year, the next two the month, and the last two the day.
Waitrose uses a simpler system, displaying the day and month directly, such as '21/01' for 21 January. Sainsbury's shows the start date of the promotion, but deals typically end on Tuesdays, giving shoppers a good estimate of when to buy.
Supermarkets also display end dates in their apps, so customers using digital tools can easily track when discounts expire. Loyalty card holders at Tesco and Sainsbury's can unlock lower prices through Clubcard and Nectar deals, respectively.
