The supermarket boosted its market share by 0.3 per cent compared with last year, from 15.6 per cent to 15.9 per cent.
Although Asda, which has a 16.5 per cent share, still holds onto second place in the supermarket stakes, its figure is on the decline. The Wal-Mart-owned supermarket giant managed 16.8 per cent last year.
Tesco is well in the lead, boasting a 30.6 per cent slice of the market, up from 28.7 per cent last year.
According to TNS, during the 12 weeks to December 4, the total expenditure within the grocery sector increased by 3.6 per cent.
On an average trip, spend is down 0.3 per cent to£15.75, while the frequency of shop visits is improving at 3.8 per cent.