Which? has produced a report that reveals the tricks that supermarkets play on shoppers to give us less value for money - without us spotting it. Over the past 12 months it has been monitoring data from price comparison websites and the stores themselves, to reveal pricing strategies that catch consumers unaware. It said that the research found that 50% of shoppers had been caught out by them.
Here are five of the worst.
1. Products shrink and prices stay the sameThis has been rife for some time now. We reported in November that Mars and Cadbury had taken chocolates out of their Celebrations and Heroes tubs but were charging the same price for them. A year earlier Nestle had done the same with Quality Streets. In 2012 Cadbury shrunk Daily Milk, and it emerged that the same thing had happened to packs of Pringles, Dairylea and Pampers.
The supermarkets say it's because the underlying cost of the products is increasing, and they are trying to make it easier to budget, but most people can't help wondering whether the retailers are benefiting in any way from the effective price hike.
2. Swapping offers on similar productsWhich? found that a number of supermarkets would offer two or three similar items, and would keep switching the offers around so that at least one of them was always on offer. This allowed customers to buy whichever was cheapest - thinking they were gutting a great deal - when in fact something similar was always available at this price.
3. Different weights cost the sameThis is most common in fresh fruit and vegetables. As the price of the food in question goes up, the supermarket simply puts them in a slightly smaller bag or box and continues charging the same amount in the hope that no-one notices. The supermarkets say it is to avoid charging more for out-of-season produce, but there's no doubt it can be hard to spot if you're in a hurry.
4. £1 signsThese are sometimes red and sometimes feature the words 'only £1', but this doesn't mean they are on offer. Many items which had been for sale for £1 for much of the year, were suddenly slapped with £1 stickers to attract shoppers. The researchers said that two in five shoppers had bought something they thought was on offer because of tactics like this - and only discovered later that they'd been confused.
5. Bigger packs but worse value
Bigger packs are often labelled as 'great value', and consumers often assume that the more they buy, the better value they will get. However, the researchers found that often when they took the time to calculate the cost, the smaller packets were a cheaper way to buy. This is exactly what the OFT warned about in 2010, and it's shocking to see that even after the supermarkets came under scrutiny from that organisation, the problem continues.
How to spot the tricksThere are three steps that you can take, which will stop you getting ripped off for good.
1. Find out what your usual purchases cost.
This may mean making a shopping list and checking old receipts to see what you usually spend on them. That way you'll have a sensible cost to compare any 'offers' to.
2. Make a note of packet sizes
You'll know how much detail you want to go into here, but if you regularly buy particular fruit and vegetables, it's worth knowing not just what you spend, but how much you get in return.
3. Take a calculator
It may seem like a faff, but if you're faced with an array of offers, or different packet sizes on your usual items, then the only way to tell what's better value is to do the maths when you're in store.
There will be those who are pushed for time, too embarrassed to do maths in a public place, or who don't think it's worth the trouble. They'll simply have to resign themselves to the fact that sometimes they will be caught out and pay over the odds.
But what do you think? is it worth taking these steps to avoid being ripped off?
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