According to the latest TNS figures, the number one retailer increased its share to 30.3 per cent in the 12 weeks to June 19 compared with 27.9 per cent a year earlier.
Behind Tesco, Sainsbury's continues to close the gap on Asda. Sainsbury's share now stands at 15.9 per cent compared with 15.6 per cent last year. In comparison, Asda has slipped from 16.5 per cent to 16.4 per cent.
The combined Morrisons/Safeway share continues to slide and is not helped by problems integrating the two businesses or the escalating feud between executive chairman Sir Ken Morrision and non-executive deputy chairman David Jones.
Morrisons' share stands at 11.7 per cent down from 14.1 per cent, which includes store disposals.
In the week before Somerfield's end-of-year results are due to be announced and a day after one of the potential bidders for the company, Universal Co-op, pulled out of the running, the retailer's board will be pleased to find the share of its Somerfield fascia has increased to 4 per cent, up from 3.5 per cent a year ago.