asda supermarket sign store GettyImages-458558077

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Asda was exclusively cheapest for blackberries and seven other lines

Asda came in cheapest for the 33 items on our list, but for the second week running it was undercut by Tesco and Sainsbury’s loyalty schemes.

Once Clubcard Prices and Nectar Prices were factored in, Sainsbury’s emerged cheapest for this week’s basket.

At £60.49, Asda offered the lowest price for 19 products and was exclusively cheapest for eight items. These included the 7up Zero, blackberries, Biotiful kefir drink and the Henry Westons cider.

Sainsbury’s was just 92p more expensive than Asda based on shelf-edge prices. It offered the lowest price for 14 items and was exclusively cheapest for the Billington’s sugar, Birds Eye chicken pies and Fox’s biscuits. Loyalty card holders, however,  would have received a discount of £2.49 – making Sainsbury’s £1.57 cheaper than Asda.

Tesco’s Clubcard users would have received a £3.64 discount on their shopping. This would have made Tesco 77p cheaper than its Leeds-based rival, but still 80p more expensive than Sainsbury’s discounted total.

At £64.08, Morrisons was £3.59 more expensive than Asda. It was cheapest for a dozen items, exclusively so for five. These included the Batchelors Smash, chicken thighs and Flora Plant Butter.

While competition was fierce between the traditional big four supermarkets, upmarket retailer Waitrose was well off the pace. At £70.59, it came in just over a tenner more expensive than Asda.

In terms of inflation, grocery prices were 9.7% more expensive than this time last year and were 0.2% more expensive than last month.

The Fox’s biscuits had the biggest jump in price (see right) – up 39% compared to August 2022. The Smash, Ye Olde Oak hot dogs and sugar were also all at least 30% more expensive than a year ago.