Aldi crowned cheapest supermarket in January

Aldi was the cheapest supermarket in January 2026, according to our latest analysis.

Each month, Which? analyses thousands of grocery prices to work out which major supermarket has the lowest prices.

Aldi was also officially the cheapest supermarket of 2025. It was the cheapest for 10 months of the 12 and was only beaten by Lidl in July and October.  

Read on to find out how other supermarkets, including Tesco and Asda, compare and how much you could save by switching supermarkets.

Cheapest supermarket in January

We checked the prices of 89 popular branded and own-brand groceries, including milk, cheese and Hovis sliced bread, at eight of the UK's biggest supermarkets throughout January to see how they compared.

The table shows how much our shopping cost on average:

Aldi was the cheapest for our shop, beating Lidl by £1.79, or £1.59 for members of the Lidl Plus loyalty scheme.

The next cheapest was Tesco with a Clubcard. It was cheaper than Asda, which doesn't offer loyalty prices in the same way as the others.

Meanwhile, shopping at Tesco without a loyalty card was cheaper than shopping at Morrisons or Sainsbury's with a loyalty card.

Tesco had Clubcard prices on 20 items on our list, while Sainsbury's was running Nectar price promotions on 14 items. Meanwhile, Lidl had three items on our list with a loyalty discount.

Morrisons and Waitrose do offer some loyalty prices to members, but there were none for items on our shopping list this month. 

Waitrose was the priciest supermarket again this month, averaging £221.53 – that's £56.79 (or 34%) more than Aldi.

• Find out more: cheapest supermarkets of 2026

What about a bigger shopping list? 

When we looked at a much larger selection (228 items), including more branded groceries, there were bigger savings with the loyalty schemes. 

Asda was knocked off the top spot for the first time in 13 months, beaten by Tesco with a Clubcard, which had loyalty prices on 107 of the items.

Sainsbury's with a Nectar card came in third place with loyalty prices on 99 products. Meanwhile, Morrisons with a More card was in fourth place with a loyalty price on just one product.

Waitrose was most expensive again, at £679.20 – 15% more than Tesco with a Clubcard. 

We couldn't include Aldi or Lidl here as they didn't stock all the branded items on our list.

You'll pay a lot more if you stock up at Sainsbury's or Tesco without a loyalty card, but only slightly more at Morrisons.

For shoppers without a Nectar card, Sainsbury's was the second most expensive after Waitrose. 

This longer list included 107 items on loyalty discount at Tesco, 99 at Sainsbury's and just one at Morrisons. 

• Interested in more than just price? Shoppers have rated product quality, customer service, online deliveries and more to reveal the best and worst supermarkets.

How much of a discount do loyalty cards give?

Based on our smaller list of products, having a loyalty card would save an average of 0.12% at Lidl, 2.14% at Tesco and 2.74% at Sainsbury's over the month.

For our longer list, which included more branded groceries and a wider selection of items with loyalty discounts, the savings were generally much more substantial – 8.13% at Tesco and 8.53% at Sainsbury's. However, savings were still only 0.14% at Morrisons. 

The discounts offered by loyalty cards may sound good, but that's only if you can access them. Our research has found that millions of people can't access loyalty promotions because they're not eligible to join supermarket member schemes due to their age, lack of address or difficulties with digital access. 

We think some supermarkets could do more to ensure certain groups of shoppers, such as those without a smartphone or under-18s, can access – or know how they can access – loyalty prices.

• Find out more: loyalty schemes compared

What's happening to grocery prices?

Annual inflation for supermarket food and drink has eased again to 4% (down from 4.3% in December), according to figures from Worldpanel by Numerator.

Prices are rising fastest for chocolate, milk, cream and fresh unprocessed meat. They're falling fastest for dishwashing products, paper products such as loo rolls and kitchen paper, and sweets.

Shoppers are also seeking out more own-label groceries: these accounted for 52% of grocery spending, the highest level ever recorded.  

• Find out more: check what's happening to prices by supermarket, category of food and ranges using the Which? food and drink inflation tracker

How Which? finds the cheapest supermarket

We check the prices of hundreds of grocery items at eight major supermarkets, using an independent price-comparison website. 

For each supermarket, we calculate the average price of each item across the month, then add those up to get each supermarket's average total price. 

What items are on the list?

Our shopping list comprises the country’s most popular and widely available groceries, based on extensive market analysis. 

It includes branded items such as Cathedral City cheddar and Hellmann's mayonnaise, as well as own-brand products like potatoes and baked beans. 

Own-brand items won’t be identical across supermarkets, but we’ve ensured everything we’ve compared is as similar as possible, based on several factors, including quality and weight.

Which? never shares the full list of products used in its analysis, as we want to avoid any attempts by supermarkets to skew the results. 

We don't want supermarkets to compete with one another to lower prices only on the items they know they'll be judged on. Instead, we want retailers to work to make groceries affordable across the depth and breadth of their available lines.

What about special offers and loyalty prices?

We include special offers but not multibuy discounts. 

We are only able to include loyalty prices that apply to all members of a scheme (where there's one price on the shelf for shoppers with a loyalty card and another for those without). Currently, this type of two-tier pricing is used at Lidl, Morrisons, Sainsbury's, Tesco and Waitrose. 

We're unable to include discounts that are personalised to selected members, and we can’t factor in points or other rewards, as these vary between customers and don't always have a quantifiable monetary value.

• Find out more: how to spend less at the supermarket

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