The consumer expert’s monthly analysis revealed that Lidl was the next cheapest supermarket, with an average shop costing £2.69 more than its fellow discount retailer.
The study checked the price of 43 popular grocery items every day at some of the UK’s biggest supermarkets, including own-brand milk, pasta and apples, plus a selection of branded groceries.
Aldi’s basket was the cheapest overall in February 2023, costing an average of £74.81, beating rival discounter Lidl by £2.69.
Waitrose was the most expensive of the supermarkets surveyed, with an average cost of £96.59, making it £21.78 pricier than Aldi.
Of the ‘big four’, Sainsbury’s was the cheapest at £85.25, followed closely by Tesco (£85.32) and Asda (£85.81).
This is the full result of Which?’s monthly analysis:
- Aldi – £74.81
- Lidl – £77.50
- Sainsbury’s – £85.25
- Tesco – £85.32
- Asda – £85.81
- Morrisons – £89.01
- Ocado – £89.96
- Waitrose – £96.59
Explaining how the comparison is carried out, Which? said: “We look at the prices of hundreds of grocery items at eight major supermarkets every day throughout the year, using an independent price comparison website.
“For each supermarket, we calculate the average price for each item across the month, then add those up to get each store’s average trolley price.
“To keep things fair, we also include special offers, but we don’t count multibuys or loyalty scheme discounts.
“Our shopping list includes branded items, such as Bonne Maman marmalade, as well as own-label cod fillets. Own-brand items won’t be identical across the supermarkets, however, so we’ve used experts to ensure everything we’ve compared is as similar as possible, based on factors including quality and weight.”