Just one-in-20 Black Friday items are at their cheapest during the shopping bonanza event, according to the Which? consumer group.
An investigation tracked the prices of 83 products on sale on Black Friday last year and found just four products had their peak discount during the November sales event.
The study looked at deals from retailers including Currys PC World, Amazon and John Lewis and in one instance found the price of a soundbar dropped by £49 pounds within a month of Black Friday.
Which? spokeswoman Natalia Hitchens said there was no evidence retailers were breaking the law, but there were concerns shoppers may become confused by the “pressure tactics” of the sales event.
“We have repeatedly shown that 'deals' touted by retailers on Black Friday are not as good as they seem,” she said.
“Time-limited sales can be a good opportunity to bag a bargain, but don't fall for the pressure tactics around Black Friday.”
She added: “Our investigation indicates that this popular shopping event is all hype and there are few genuine discounts.”
However Amazon has disputed the report, which claimed the company’s Amazon Echo could be found for less outside Black Friday.
“The claim from Which? with regard to Echo is false and we have made this clear in our response to them,” an Amazon spokesman said.
“Amazon.co.uk customers were not able to buy the Echo (2nd Gen) device cheaper before Black Friday 2018.”
Currys PC World said it had never suggested all products would be at their cheapest.
“When we launched our Black Friday event last year, 40 per cent of those products were the lowest price they had ever been,” a spokesperson said.
John Lewis said it offered customers “the best value on the high street all year round, including during the Black Friday period”.
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