The price war has made the grocery market contract for the first time in 20 years, figures from Kantar Worldpanel revealed this week. The winner of that price war in this week’s Grocer 33 is Asda but, for the second week in a row, vouchering is keeping Tesco within touching distance when it comes to saving shoppers money - if you’re a loyal Tesco shopper at least.

Tesco was £3.97 more expensive than Asda, but our mystery shopper received a £4.64 Price Promise coupon for their next Tesco shop. Standout products at Tesco included eggs 35p cheaper than at Asda and Kettle Chips, which were £1.18 cheaper. However, Asda, which has pledged to plough an extra £500m into price cuts this week had 16 promotions and almost half of the G33 basket (14 products) at an exclusively low price.

Morrisons’ £58.10 basket was 5% more expensive than Asda’s, but did offer 13 products at the cheapest price, four exclusively so. However, the greatest saving was just 10p, separating Morrisons’ sugar snap peas from those at Asda.

Despite 12 promotions, Sainsbury’s was £6.36 adrift of Asda, and most expensive for seven products - though it did have more price-only promos (four) than any other retailer. However, like Tesco and Waitrose - which came in at just under a tenner more expensive than Asda - it was exclusively cheapest for only two products.