The hype around Black Friday creates the impression that every offer is worth trampling over fellow shoppers to get to, with retailers slashing prices to historically low levels for one day only. But our research has found that's rarely the case.
In 2020, our revealed that 98% of the discounts advertised the previous year - including promotions on popular tech, home and personal care products - were available for the same price or cheaper in the six months after the sales.
And, while you might expect some products to fall in price over time, we also found that 85% of the items had also been the same price or cheaper in the six months before Black Friday.
In fact, just three of the 119 products we tracked - that's 1% - were at their very cheapest price on Black Friday.
So before you rush into impulse-buying a discounted coffee machine or tablet, read on for our advice on how to work out if a deal is real.
This is the most basic check you can do, but our research found that 13% of Black Friday shoppers didn't do this in 2017.
We've often found that more than one shop will sell a product at a similar price, but only one claims that the price is a special offer.
For example, if four shops are selling the same for £250, but only one is claiming it's a special offer at 'Now £250, was £300', it's a pretty good indicator that the price is not a particularly special deal.
Of course, if you're happy to pay £250 for that particular washing machine, that's fine. But don't snap it up thinking you're getting a bargain.
This will enable you to know whether Black Friday prices are genuinely worth getting excited about.
Claims such as 'was £100, now £50' are abundant on Black Friday. But don't let these 'anchor prices' mislead you.
Retailers shout about savings - often in red to grab attention - as a way of influencing customers and they can be quite misleading.
When we looked at items on special offer across major retailers for the first half of 2020, we found that several products were listed at their lower price for longer than they were at their full 'was' price.
We've also found retailers using old RRPs (recommended retail prices) as 'was' prices, so they reflect the value of the item when it was first released, not its current value.
And Amazon displays every price reduction as if it was a promotion, so even a price drop as small as 1p will be flagged as a discount.
Rather than automatically trusting anchor prices, it's better to check against other shops' prices to try to work out the true value of the item you're buying.
The rules that govern special offers are vague. In some instances, shops can get away with using 'was' prices that haven't been in place for a long time if they put up a sign explaining the deal. Tactics such as this can make offers look better than they are.
We've seen notes that explained the product was actually only at the higher price for a fortnight, six months before the current offer.
Sometimes these notes are well flagged, but sometimes they're completely buried - meaning we've had to scroll through masses of small print to uncover vague wording - so it's worth doing some thorough research if you want to be confident you're getting the best deal.
When we checked promotions in 2020, AO.com had its explanations below the item description, specification and customer reviews, while at Currys they were in a small grey font.
Not all manufacturers have RRPs, but some do and choose to display them on their own websites. Before you buy a product in the sales, check the manufacturer's website to see if you're getting a decent discount on the RRP.