Lidl was the cheapest supermarket in January, according to the latest monthly analysis from Which?.
We compared prices for a basket of 23 items every day last month and found that, on average, shoppers would have paid £24.78 at Lidl. It beat rival discounter Aldi by just 59p.
Meanwhile, the most expensive supermarket was more than £9 pricier than Lidl for an equivalent basket of groceries. Here, we reveal the month’s cheapest and most expensive supermarkets.
Cheapest supermarket for a basket of groceries
Every day throughout January we checked the prices of 23 items, including own-brand products such as apples and eggs as well as branded goods such as Hovis wholemeal bread, to see how the UK’s biggest supermarket chains compared.
Here’s how much our basket cost on average:
At the other end of the scale, Waitrose was more than £9 pricier than Aldi, at £33.94 – that’s 37% more.
Groceries with some of the biggest price differences included own-label seedless grapes, which had a difference of £1.26 between Lidl and Waitrose, and own-label melon, which had a difference of 95p.
Of course, price is just one factor when you’re deciding which supermarket to shop at. We also survey shoppers on their experiences of supermarkets’ product quality, customer service, store experience, online deliveries and a range of other factors to reveal the best and worst supermarkets each year.
How do bigger shopping lists compare?
We also compared a trolley packed with 68 items (the original 23 plus 45 more). This included a greater selection of branded items, including Cathedral City cheddar, that aren’t always available in the discounter supermarkets – so for our bigger trolley we haven’t been able to include Aldi or Lidl.
Asda, at £133.34, was easily the cheapest of the traditional supermarkets. It was £15.93 cheaper than the most expensive supermarket, Waitrose.
We can’t compare exactly the same items each month because products aren’t always available at every retailer, but Asda has been the cheapest mainstream (non-discounter) supermarket for 25 months now, having claimed the title every month since January 2020.
How Which? compares supermarket prices
We check the prices of hundreds of grocery items at eight major supermarkets every day throughout the year, using an independent price comparison website. For our ‘cheapest supermarket of the month’ analysis, we work out the average price for each item at each supermarket across the month, and add the averages up to get an average trolley price for each store. We include special offer prices but not multibuys, to keep it as fair as possible.
Our shopping list combines branded items such as Kenco coffee, Oxo stock cubes and Twinings English breakfast tea with own-label products, including onions and milk.
Of course own-brand items aren’t exactly the same at different supermarkets, but we’ve used experts to ensure that the products are as comparable as possible based on a range of factors, including weight, quality and other industry data.
What you need to know about inflation
Every month sees further concerns about rising grocery prices.
The latest figures from market analyst Kantar show grocery price inflation at 3.8% in the four weeks to January 23. Its research showed prices are rising fastest for savoury snacks, fresh beef and crisps, but falling for bacon, vitamins and beer.
There’s been fierce debate this month about the extent to which inflation hits different people, with food commentator Jack Monroe saying rising prices hit the poorest people the hardest.
Tips to help save money when supermarket shopping include switching from branded to own-label products, trading down ranges for own-label food and drink (for example from premium to standard or standard to budget), and using large supermarkets rather than convenience stores.