Sainsbury’s is priciest supermarket for a big shop, says Which?

Sainsbury’s is the priciest supermarket for a big shop if you don’t use a loyalty card, according to claims by Which? in its most recent analysis. 

The grocer overtook Waitrose for the first time in the monthly analysis, which has been running for years, becoming the most expensive supermarket to buy a trolley full of groceries from.

Asda remained the cheapest non-discounter supermarket, £33.52 cheaper than Sainsbury’s. 

Which? also compared the price of a basket of 39 items. Aldi was the cheapest, with a total average cost of £67.72. 

Every day in September, Which? compared the cost of a large trolley of 131 items. This included branded items, such as Andrex toilet paper and Cathedral City cheese, as well as own-label groceries. Because branded groceries aren’t always available in discounter supermarkets, Aldi or Lidl couldn’t be included in this comparison.

Asda was found to be the cheapest ‘traditional’ supermarket, with £325.71 on average for a big trolley shop, beating next-cheapest Morrisons (£332.22) by £6.51.

Sainsbury’s was £33.52 more expensive than Asda, coming in at £359.23 for the same trolley of comparable goods – this is the first time it has overtaken Waitrose to come out as the most expensive.

Some 39 of these popular groceries, including Heinz baked beans, milk and bread, were also available at Aldi and Lidl, so WHich? ran a smaller basket comparison including these two discounters to see how they compared. 

Aldi was the cheapest overall, with the shop costing £67.72, beating rival discounter Lidl by just £1.24. This is the 16th month in a row that Aldi has been the cheapest supermarket.

The same shop at Waitrose was £84.37 on average, making it £16.65 – or 24.6% – more expensive than Aldi. 

In this smaller basket analysis, Sainsbury’s sat in the middle of the table, coming in fifth-cheapest or fourth-priciest. Of the ‘big four’ supermarkets, Asda was the cheapest, at £75.42.

However, Sainsbury’s has refuted the research, claiming that the company cherry-picked 131 products while also not revealing to the grocer what products had been surveyed.

A Sainsbury’s spokesperson said: “These claims are entirely false and insulting to the millions of savvy customers who choose to shop with us every week. There is an overwhelming amount of independently verified data showing the great value customers get when shopping at Sainsbury’s. We are disappointed that Which has refused to share its data with us and has instead chosen to mislead customers by choosing to exclude Nectar Prices promotions in its research.

“The vast majority of our customers are shopping with Nectar Prices and have saved £400m on their shopping in the last six months. Customers can be sure they are getting great value every time they shop with us.”