Aldi has been crowned the cheapest UK supermarket for the twelfth month in a row by Which? consumer champions.
The price of a basket of 40 goods came to £68.60 at the discount supermarket in May.
This was £18.31 cheaper than the most expensive store, Waitrose which had a basket price of £86.91 for the same shop.
Second place was taken by Lidl who missed out on the top spot by £1.91 with a basket price of £70.51.
Asda was the third cheapest (£76.45), followed by Sainsbury's (£77.13), Tesco (£77.56), Morrisons (£79.09), and then Ocado (£83.90).
Which? also compared the cost of a larger trolley of 131 items which includes the original 40 products from the basket comparison plus 91 more.
Asda was the cheapest once again for the larger trolley comparison with a price of £332.40 in May.
Asda has managed to hold onto this title since January 2020.
Morrisons took second place with a trolley price of £334.47, Sainsbury's came third with an overall price of £341.40, Tesco fourth at £349.35, and Ocado fifth at £354.90.
Waitrose was again the most expensive supermarket chain with a trolley price of £363.99 - which is a difference of £31.59 or 9.5% more compared with Asda.
Ele Clark, Which? Retail Editor, said: "The Which? Food Inflation Tracker shows that the price of food and drink is continuing to soar, as people suffer through the worst cost of living crisis in decades. It's no surprise to see many shoppers turning to discounters like Aldi and Lidl when our research shows they could make savings of more than £18 on a basket of everyday groceries.
Which? once again called out the major supermarkets for not doing enough to help shoppers during the current cost of living crisis.
The consumer champion said the latest price analysis demonstrated that shoppers can make considerable savings on their groceries depending on where they buy their food.
This is because budget ranges and prices at the discounters are rising significantly, and the traditional supermarkets' convenience stores are still failing to offer or stock budget lines.
Ms Clark added: "Supermarkets aren't currently doing enough to help shoppers."
"Which? believes the big retailers have a responsibility to ensure everyone has easy access to basic, affordable food ranges at a store near them, and to provide transparent and comparable pricing so people can easily work out which products offer the best value."