Supermarket pricing review launched after Which? investigation

Our research has uncovered poor, inconsistent and sometimes missing unit pricing on groceries across a range of supermarkets. The Competition and Markets Authority will look into this as part of an official review.

Unit pricing enables shoppers to compare value by the cost per unit (for example per 100g or 100ml) to help find the best deals. 

Our Affordable Food For All campaign calls on supermarkets to commit to clear pricing, better access to budget ranges that enable healthy choices, and more offers for those who need them most. 

• Do you want to see your supermarket take action? Sign the petition.

Supermarket pricing investigated

The Competition and Markets Authority (CMA) will look into grocery unit pricing practices online and in-store. It said the cost of living crisis meant it was important that shoppers were able to compare products like for like. 

This follows our 2015 groceries super-complaint, where the CMA looked into pricing and promotional practices in the groceries market.

It concluded that complexities and inconsistencies with unit pricing could prevent people from spotting which deal gives them the best value. These included differences in how unit prices are presented and labelled between retailers, and inconsistencies with how retailers present unit prices for similar products and those on promotion.

The CMA said: 'We know the increased cost of living has hit the pound in people’s pockets. That’s why we’re pressing on with this important grocery unit pricing work to ensure shoppers can more easily compare prices and make choices that are right for them.'

The latest CMA review will consider the following:

• whether the unit pricing issues identified during the 2015 super-complaint remain
• compliance with the law by retailers
• consumer awareness and use of unit pricing information.

The CMA will provide an update on the case later in 2023.

Can you spot the cheapest supermarket groceries? 

A Which? investigation in August 2022 found that unit pricing is often unclear, inconsistent or absent. 

We quizzed shoppers across the country and found that 72% of them couldn’t spot the cheapest fizzy drinks in a range of real-life examples from supermarkets.

That's important, because our research also showed you could pay up to 346% more by going for different sizes of exactly the same product. If you know the price per 100g or 100ml, you can see which is the cheapest straight away - but if unit pricing is missing it can be tricky to figure out. 

• Find out more: can you spot the cheapest groceries?

What our investigation found

Supermarkets are legally required to provide unit pricing on most items, under the Price Marking Order 2004. 

But even when supermarkets stick to the rules, there are still gaps that create confusion for shoppers. We trawled nine major supermarket stores (Aldi, Asda, Iceland, Lidl, M&S, Morrisons, Sainsbury's, Tesco and Waitrose) to see how unit pricing was working in practice.

We found a multitude of issues, from Tesco steak to Penguin bars at Waitrose and confectionery in Iceland. 

These included: 

• differing units used for the same types of items 
• confusing terminology 
• missing unit pricing 
• unit pricing that was hard to read 
• no unit pricing on multibuys
• no unit pricing on loyalty prices.

Which? calls to improve pricing

We've campaigned on the issue of unclear pricing before, culminating in a super-complaint to the Competition and Markets Authority in 2015. 

This led to a series of recommendations to improve unit pricing in supermarkets – but the legislation itself wasn’t changed, and our research shows there’s still a lot more to be done. 

We believe clear unit pricing is key to helping shoppers through the current cost of living crisis, and we're calling on supermarkets urgently to do more by making unit pricing more prominent, legible and consistent – as well as by displaying it on their promotional offers.

Sue Davies, Which? Head of Food Policy, said: 'Grocery prices are a huge concern, as households all over the country grapple with the cost of living crisis, so it’s timely and important for the CMA to be looking at whether prices are clearly and fairly displayed at the supermarket.

'We know poor, inconsistent and sometimes missing price information is a problem, and that's why Which? is campaigning for pricing transparency from supermarkets, so that shoppers can easily work out which products are the best value.'

• Find out more: Which?'s Affordable Food For All campaign