German-owned discounters Aldi and Lidl, No. 2 player Sainsbury's (SBRY.L), and market leader Tesco (TSCO.L) were the biggest winners among British supermarkets at Christmas, according to industry data published on Wednesday.
Market researcher Kantar said those performing not so well included Asda, Morrisons, Waitrose and Iceland.
Marks & Spencer (MKS.L), which analysts believe performed well, is not included in Kantar's monthly data set.
The researcher said that over the 12 weeks to Dec. 24, Sainsbury's sales were up 9.3% year on year, pushing up its market share to 15.8%, its highest since December 2020.
Tesco's sales rose 7.5%, and its market share edged up 0.1 percentage point to 27.6%.
Shares in Sainsbury's, which have gained 33% in the last 12 months, rose 1.6% in early deals. Tesco, which has seen a 28% share price rise in the same period, traded up 1%.
Kantar recorded Lidl's sales growth at 13.8% and Aldi's at 9.9%, increasing their combined market share to 17%.
Lidl and Aldi on Tuesday reported sales growth of 12% and 8% respectively for December.
Kantar said a record 13.7 billion pounds ($17.3 billion) passed through UK supermarket tills over the four weeks to Dec. 24.
Total take-home grocery sales grew in value by 7.0%, a figure largely driven by inflation, which slowed to 6.7% in the period from 9.1% in last month's report, the fastest month-on-month drop that Kantar has recorded and its lowest level since April 2022.
"The rate of inflation is coming down at the fastest pace we have ever recorded, but consumers are still facing pretty hefty pressures on their budgets," Fraser McKevitt, Kantar's head of retail and consumer insight, said.
Sales measured by volume, or the number of items bought, rose 2% over the four weeks.
The researcher said the average household spent an all-time high of 477 pounds in the period, up 28 pounds on 2022.
Nearly one third of all spend was made on items with some kind of offer, the highest level since December 2020.
Kantar also highlighted especially strong performances from supermarkets' own-label lines, with sales of premium ranges like Sainsbury's Taste the Difference and Tesco Finest surging by 11.9% over the 12-week period compared with last year. Branded sales rose 6.0% during the same period.
Online's share of the market held steady at 11.6%.
Sainsbury's is due to report on Christmas trading on Jan. 10, with Tesco and M&S updating on Jan. 11.
UK supermarkets' market share and sales growth (%)
Source: Kantar
($1 = 0.7915 pounds)
