Asda has been named the cheapest supermarket for branded items for a second month, with shoppers paying over £3 less for one popular olive oil than at Waitrose.
According to Which? analysis, a basket of 241 commonly bought items came to £813.16 at Asda in March. The supermarket beat both Tesco and Sainsbury's membership prices to gain the top spot again.
The research also pointed to big price differences on certain products depending on where customers shopped.
Filippo Berio boss Walter Zanre told Money earlier this month that supermarkets were "taking the mickey" out of shoppers by not passing a reduction in olive oil costs on the prices at the shelves.
Which? found a 500ml bottle of Filippo Berio classic olive oil was £4.98 on average at Asda compared to £8.51 at Waitrose, a £3.53 difference (71%).
Its extra virgin olive oil (750ml) was cheapest at Morrisons, where it cost £7, and most expensive again at Waitrose (£11.35), a difference of £4.35 (62%).
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Tilda boil in the bag basmati rice (four-pack) had the biggest price difference again last month, costing £1 at Tesco without a Clubcard and £2.25 at Waitrose, a 115% difference.
When it came to the most expensive supermarket for branded groceries overall, however, Sainsbury's was top with a basket price of £933.82 when Nectar membership card prices were excluded.
Reena Sewraz, Which? retail editor, said: "If you're loyal to specific brands, the current market is a bit of a lottery.
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"You could easily end up paying double for the exact same jar of coffee or bag of rice depending on where you shop. While membership cards offer targeted discounts, Asda's straightforward pricing is proving more reliable for fans of big brands who want to keep their grocery bills under control without the need for a card."
A spokesman for the John Lewis Partnership, which owns Waitrose, said: "We consistently offer great value on our customers' favourite brands. This assessment only provides a snapshot, and does not take into account the wide range of promotions on other products belonging to the brands included within this analysis."
(c) Sky News 2026: 'Taking the mickey'? £3.53 difference for same product as cheapest supermarkets for bra
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