21 of 50 retailers used sale, low-stock or popularity claims
Which? found flash sales, low-stock alerts or popularity claims on the websites of 21 of the 50 biggest UK retailers it checked. Some sale prices carried on after the sale was due to end, and some messages about how many people had added an item to their basket did not match a test by 18 volunteers.
Which? said on 13 October 2026 that it had checked the websites of 50 of the biggest UK retailers and found flash sales, low-stock alerts or popularity claims on 21 of them. In its investigation into pressure selling, it said none of the retailers explained how they defined the terms they used.
On Amazon Marketplace, a balance board was advertised on 3 August in a "lightning deal" at £134.99, ending in 6 hours. The board was still £134.99 the next day, and for the following 5 days.
On Shein, an eyeshadow stick was reduced by 49% to £2.26 in a sale due to end at 5pm on 4 August. The sale was extended to 7 August, then to 8 August, and the price stayed at £2.26 throughout.
Which? asked 18 volunteers to log in at the same time and add the same products to their baskets. At John Lewis, all 18 volunteers viewed and added a frying pan. A message saying "six customers added this to their basket in the last 48 hours" did not change at first, and an hour or so later it showed 15.
At M&S, all 18 volunteers added a tie and handkerchief set to their baskets. An hour and a half later, a message said the set had been added to bags 12 times in the last 5 days.
A Deltapoll survey of 2,053 members of the public for Which?, carried out from 14 to 17 August 2026, found that:
- around 3 in 10 (30%) had seen a sale countdown clock in the past year, and more than half of those had little or no trust in them
- about 4 in 10 had seen a low-stock warning, and 7 in 10 of those said it influenced their buying decisions
- about 4 in 10 had seen claims about how popular a product was, and about 6 in 10 of those said the claims influenced their buying decisions
What the companies say
Amazon told Which? that the balance board deal ended as scheduled and the seller lowered the board's usual price the next day. Amazon said third-party sellers set their own prices.
Shein said it launched an internal review as soon as it became aware of the problem with the sale and fixed the error. It said it had taken action to make sure its promotions follow guidance from the Competition and Markets Authority (CMA).
John Lewis said its online prompts are a helpful guide to popular items and it makes sure they are accurate. It said there is a short delay before the figures go live.
Which? said it understood that the M&S "added to bag" messages were based on genuine customer activity processed in real time, but that tracking and consent settings may mean some activity is not recorded. It said M&S could not conclusively explain why the message showed 12 when all 18 volunteers had added the set.
What it means for consumers
Which? said the CMA's view is that countdowns where the sale price carries on are misleading. Hayley Fletcher, the CMA's director for consumer protection enforcement, told Which? that the rules are clear and that a claim made to shoppers needs to be true.
The Digital Markets, Competition and Consumers Act 2024 bans unfair commercial practices, and its list of practices that are always unfair includes falsely saying a product is only available for a limited time. If a misleading claim was a big reason someone bought something, they may have the right to cancel and get a refund, usually within 90 days, or to get a discount or compensation. Our guides explain how to get money back after being misled into buying and how to return something bought online.
What happens next
Which? is sharing its findings with the CMA, which it said has new powers to order businesses to pay compensation to affected customers and to fine companies up to 10% of global turnover.