Food sales climbed by 3.8% over the summer, boosted by the heatwave and the World Cup.
Aldi put on the greatest growth in period to September 9 when its sales advanced 13.9%, nearly half of which came from the fresh and chilled categories. Its market share was up 0.6 percentage points to 7.6%.
Asda was the best performer among the big four grocers, delivering a 3.1% increase to achieve a market share slightly down at 15.3%.
Overall, shoppers spent £228 million more on alcohol, £178 million more on soft drinks and £74 million more on ice cream between the World Cup kick-off through until the August bank holiday
Consumers’ preference to stay close to home mean that supermarkets’ c-stores increased sales by 7.6%.
The Co-op was a “particular beneficiary”, generating a sales uplift of 8.5% - its best showing since 2011 – to claim a market share up 0.3 percentage points to 6.6%.
Tesco’s sales rose 1.9%, while its market share was down 0.5 points to 27.4%.
Sainsbury’s revenues rose 1.6% and its share was down 0.4 points to 15.4%.
Morrisons’ sales climbed 3% and its market share was down 0.1 points to 10.2%.
Promotions accounted for 32.4% of grocery sales, the lowest level since June 2009.
Grocery price inflation stood at 2%, adding £1.64 t household’s weekly shopping bills or £85 annually if sustained.
Grocery market data from Nielsen showed a 1.4% rise in sales by volume in the four weeks to September 8.