/ Food & Drink, Shopping

Which? doesn’t run a supermarket, but if it did…

Which? supermarket shelves

We’re calling for supermarkets to Price it Right. To show how complex some unit price comparisons can be, we created our own supermarket to put shoppers to the test. Could they work out the best value?

For one night only, we turned a stately conference room into our very own Which? supermarket. Wood panelling and smart portraits adorned the walls, but our bright red supermarket shelves packed with ‘Price it Right’ emblazoned food stole the show.

We gathered together shoppers from across the UK and representatives from some of the major food retailers to talk about supermarket unit pricing and how it could be improved. Our very own executive director, Richard Lloyd, kicked off the debate and set a challenge for our guests…

But I’m getting carried away. If you haven’t read any of our previous Conversations about this topic, you might be wondering what unit prices are. A unit price is the price of food displayed using a consistent measure, such as per litre or kilo. At the moment, it’s harder than it should be for shoppers to make informed choices because this information isn’t always consistent or easy to see.

We know that food prices are a big concern for people. We believe it should be straightforward for shoppers to compare the price of food. Our gallery shows examples of poor unit pricing that we’ve found in our research.

The Which? supermarket sweep

So what was Richard’s challenge? Well, we gave each team a basket and a shopping list, and asked them to scour the Which? supermarket for the best value items. You can see how they got on in our video:

Our shoppers relished the challenge, but they were frustrated by the difficulties they encountered when trying to find the best value bananas, tomato ketchup and chocolate bars. One of the shoppers said:

‘Normally you’d just be attracted by what looks like the cheapest, it’s only then sometimes when you look at it more closely that it’s not quite the deal it’s making itself out to be and that’s what I find frustrating. If it’s a deal, tell me it’s a deal, don’t try and trick me.’

Morrisons and Sainsbury’s are pricing it right

Before we launched our Price it Right campaign, all of the major ten retailers were displaying unit prices in ways that made it difficult for shoppers to compare products and find the best price.

Morrisons shelf label after supporting our campaign to Price it Right Sainsbury's new price label for apples

Recently, Morrisons has started rolling out new labels for its shelves, making prices much easier to compare. And it’s not just Morrisons – Sainsbury’s is also rolling out new labels to help customers shop for fruit and veg without needing a calculator. There are some examples of their new labels on the left.

It’s brilliant that Morrisons and Sainsbury’s are bringing new, clearer shelf labels to their customers. We want every supermarket to do the same.

Have you spotted any confusing pricing labels in your local supermarket? If you shop at Morrisons or Sainsbury’s, have you noticed their new shelf price labels?


My local Sainsburys displayed the unit price of their normal (effectively By Sainsburys, but not necessarily branded as such) mango chutney as 5p per 100g until after a whole month of complaints from me they finally corrected it to 35p per 100g. Their “How Well Did We Do?” website makes it very hard to make specific complaints. All I could do was to introduce my complaints as reasons for a low score out of 10, and there was no response. Using @sainsburys on Twitter got some response including irrelevant requests for the barcode. I supplied this the first time but after that I was using the Basics product. I kept tweeting “Just look at the shelf ticket”. I have found that tweets to @sainsburysPR are the most effective, because external PR professionals are following it.

I politely point out mistakes to a sales assistant and get them to remove price labels that are incorrect. If there is no-one near, I just remove shelf labels and hand them in at the customer services desk.

I recently pointed out a mistake and the sales assistant came back with a newly printed label within a few minutes.

No tweeting required.

Tesco manage to get prices wrong all the time, you’d think they’d have someone check them or at least one of the thousand or so people who put the price stickers on the shelves raise it with senior management.

Some fine examples of their incompetence can be found https://www.facebook.com/pages/Tesco-Offer-Fail/109092949114632

In my view, in the Sainsbury tag above the “per kg” is far too small relative to the price. However, if and when a time comes when we can be certain the they have not done a “Tesco” and snuck in a “price per lb” with the “lb” so small it can be missed. then this would be accepteble.
This time can never come untill and unless the UK government make it a specific offence the use non metric units at any point in the retain market place.
OK, I know that will never happen, especially with Which? lobbying the government to keep old and outdated units. I can dream though.

Thanks for publicising the problems we have with supermarket pricing and giving praise for good practice.

One of the main problems is failure to give a unit price for a multi-buy offer, only for the individual item. It’s not rocket science and is something that could be sorted out very quickly.

I don’t condone pricing of one item in grams and the other in millilitres, though for many products they are more or less interchangeable. The obvious solution is to sell all supermarket products by weight, which may not seem intuitive but there is no reason why this could not be done.

As for the shopper who did not know how to interconvert grams and kilograms – I give up hope. 🙁

I was in Aldi recently and wanted to buy fresh fruit and vegetables but was put off by the price signs hanging from the ceiling above the produce. I could not match the description of the produce with the description on the price sign above the produce. I thought a 250g of plum baby tomatoes was 79p as no other price was displayed for baby tomatoes. Also I could not see the weight on the label as it was too high and too small. When I got to the till and saw the price was 99p, I told the cashier to remove them from my bill as the price was not clearly displayed by the produce.

When shopping in Aldi and Lidl, I often fail to identify the correct price because of the slap happy way they have of showing prices.

Good point, wavechange. Customers may not take up an offer because a lower unit price is not provided for the offer. As the supermarkets presumably want to shift more volume through these special offers you would think they would realise that it is in their interest to publish the special offer unit price. Sainsburys used to have a weird policy of giving some prices per 100g and others even for similar products per kg. As I hear they have new price labels I shall look more closely. I have noticed bags of 6 citrus fruit and the like now unit priced per fruit. I once overheard a customer by the loose bananas asking a staff member the unit price. Size varies, of course, but 11-15 pence would do it at the moment, I think.

It serves them right if customers don’t buy because the unit price is not provided for the goods on offer.

I suspect that the unhelpful pricing is done to help create a state of confusion in the minds of customers, so that they are discouraged from working out which products are the best value for money.

I agree. I’m a lb and oz person and do know how many grams are in a kilogram and how many are roughly the same as a lb. However I can’t understand why similar items can be labelled in either ml or mg. I also have to weigh up how I feel about the packaging!

A kilogram (kg) is 1000 grams (g), in the same way that a kilometre is 1000 metres. The metric system makes life very easy.

A pound is 454 g. I remember this from many years ago: Two and a quarter pounds of jam weigh about a kilogram.

For most supermarket products, you can assume that millilitres (ml) and grams (g) are about the same. It would be great help if manufacturers and retailers used grams for everything we buy in supermarkets.

Well done, wavechange, for trying to educate everybody. I was born in 1950 and had to convert to metric twice at school (or was it school and university), first to the cgs (centimetre, gramme, second) system and then to the latest metre, kilogramme, second, version with its much bigger but relatively reasonable units. It is beyond me how anyone younger than age 62 cannot handle metric units.

Thanks johnecon. I’m around the same age and have shared the same experience. Having spent years in teaching before I retired, it is very difficult to switch off. 🙂

Do come and join us in the debate about metrication, which I regard as one of the most entertaining Converations:

In this and the previous Conversation, several contributors demonstrate remarkable ingenuity in supporting continued use imperial units.

lessismore, ml is a liquid measure and mg a weight one, as are litres and kilogrammes respectively. Thus gels, etc. are often sold in tubes marked in ml. Knowing the volume of a potato, however, is of little use. Only when the substance contained has the same density as water is the number of ml the same as the number of mg. Heavier than water the ml are fewer than the mg, lighter more. In my opinion it is only really important to know the volume of a liquid if you are going to have to measure it out into a measure marked in volumes. Weighing out cough medicine would be a real pain. Americans have to have recipes in cups so that they do not have to weigh anything.

Good point about the cough medicine, johnecon. Measuring that by weight would be fun.

I became accustomed to measuring liquids by weight when I worked in a research lab. I did this because it’s usually just as easy and always more accurate. Ever since I have had digital kitchen scales, I have measured liquids by weight when cooking.

wavechange, please don’t mention weighing things in laboratories. It brings back terrible memories of smaller yields than I should have got in organic chemical synthesis at university and getting varicose veins in my early twenties because of standing up in labs all afternoon while the modern languages students were thinking about getting out of bed for !afternoon! lectures. I refused all research jobs, started work in the City and am now an oil and gas economist.

Research becomes more interesting when you design the experiments and others do the standing in the lab. 🙂

Meanwhile, back on topic….

While searching for relevant information in the news, I found that supermarkets (except Asda) are planning to get rid of confusing multi-buy deals, after an investigation by the Office of Fair Trading:


Richard says:
15 May 2013

I’ve notice a change for the better in recent weeks at my local Sainsbury’s (Winchmore Hill, London). Fruit and sweets seem to be priced and unit price is shown. The Which? campaign is having a good effect. Let’s hope it continues.

Bella says:
27 May 2013

Three days ago I noticed that the Sainsburys website is calculating the price per 100g for olives incorrectly. Sainsbury’s Pitted Black Olives 185g are shown as £0.56/unit, £0.66/100g. On the MySupermarket website they’re shown correctly as Sainsbury’s Pitted Black Olives (185g) 56p (30.3p/100g). I spent a while checking other items and found that this problem is rife among the olives – probably elsewhere too if I know anything about computers! The more I checked the more annoyed I became as this calculation isn’t exactly rocket science and the error makes a nonsense of Sainsburys claim to be making it easy to compare prices and find the best buy. By the time I went back to my shopping, half the contents of my basket had disappeared, shortly to be followed by the rest. I decided to shop at Tesco instead and phoned Customer Services to express my annoyance. The person I spoke to said he’d email the website people about the error but it still hasn’t been corrected. Watch out at Sainsburys Online! Do your own calculations (though this shouldn’t be necessary, for goodness sake!) or check prices on MySupermarket.co.uk.

I wish the supermarkets would obey the law, and stop selling milk in plastic bottles in two-pint containers AND litres right next to each other on the same shelves. It’s totally random what kind of bottle you’re likely to pick up and unless you check the “price per” sticker (if you can even find it) very difficult to see the true price comparison.

Selling milk by the pint is illegal dammit. Oh – I know, they’re not selling it by the pint, they’re just selling it in a 1135mL container with a big prominent “2” on the front (without the word ‘pint’). But that’s just gaming the system. And for what? Who cares what the units are anyway – just we’d surely all like to have two bottles that *look* the same actually *be* the same.

And since this is the 21st century and all that, we’d expect litres and multiples theof wouldn’t we? Every other fluid in the shop is sold like that.

Except (oddly) Evaporated Milk which is sold by the gram! Why is that??

You’ll love the coffee I saw this week – Taylors of Harrogate espresso beans 1 kilo bag is £1,499 per 100g and the mis-priced Maximuscle £33.60 for 908g = £33.60 per kilo, is still wrong FOUR MONTHS later, despite reporting it 5 times!