Asda’s sales decreased by 4.2%, during the 12 weeks to 28 December 2025.

According to the year-over-year data from Worldpanel by Numerator, Co-op also saw a sales fall of 1.3% during the period.

Ocado continues to be the fastest-growing grocer, with sales increasing by 15% over the 12 weeks to 28 December 2025 year-over-year, and now holds 2.1% of the market.

Lidl experienced a 10% sales increase and accounts for 7.8% of the total market share.

Sainsbury’s and Tesco’s market shares grew to 16.3% and 28.7%, respectively.

Aldi remained flat in market share year-over-year at 10.1%, and Waitrose increased to 4.7% from 4.6%.

Fraser McKevitt, head of retail and consumer insight at Worldpanel by Numerator, said: “Easing inflation helped to take the edge off the cost of Christmas this year, giving households a little more room to spend.

“It was a Christmas of smart savings and considered choices – almost every household bought into supermarkets’ premium ranges, while price remained front of mind. Discounters enjoyed their biggest-ever Christmas share, and shoppers leaned on their loyalty cards to get the best deals.”

The data also found that grocery sales reached a record £13.8bn in the four weeks to 28 December 2025, increasing by 3.8% year-over-year.

Grocery inflation was 4.3%, with the average spend at supermarkets during the festive month reaching £476, which was an additional £15 in comparison to December 2024.

Premium private label products were popular among shoppers, exceeding the £1bn milestone in December, with a growth of 9%.

The highest amount spent was on fresh meat with £115m in sales and chilled snacks with £80m in sales.

Additionally, spending on promotions increased to 33.3% from 32% last year, with households spending an additional £36m on discounted fresh vegetables.

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