Lidl 'easily' won a price comparison challenge which saw it named cheaper than five major supermarkets.
The Grocer runs a shopping survey, where it compares the cost of a basket of 33 goods at Asda, Tesco, Morrisons, Sainsbury's and Waitrose.
Usually, Aldi and Lidl are not involved, but the popular German-owned supermarkets have been included separately as "guests" in recent weeks.
Aldi triumphed as a guest in late May and the following week it was Lidl's turn.
The Grocer says Lidl offered the lowest price on 26 items, included six branded items, which The Grocer described as an "easy victory" for Lidl in the challenge.
The 33 item shop cost £50.64 at Lidl, a £7.62 saving on the same shop at Asda, which came second.
The Grocer says : "This made it [Lidl] 13.1% cheaper than the Leeds-based [Asda] supermarket and was a bigger winning margin than the 12.5% notched up by Aldi last week."
Morrisons came in third, with a shop there costing £9.75 more than in Lidl, although Morrisons was the cheapest for potatoes.
Tesco ranked fourth, at £60.88 for the shop, which was £10.24 more than Lidl.
Although Clubcard users can slash some of the price of a Tesco shop, the trolley of goods still cost £7.79 more at Tesco than Lidl, with a Clubcard discount applied.
The Sainsbury's shop came in at £61.90, 18.2% and £11.26 more expensive than Lidl, while the Waitrose shopping list was £21.32 more costly than Lidl's, at £71.96.
