Sainsbury’s was the only grocer among the big four to grow share in the four weeks to May 25, while Aldi recorded the strongest sales growth in the sector.

Sainsbury’s share rose from 16% to 16.1% while sales at the grocer jumped 4.9%.

Waitrose and Aldi recorded the largest jumps in share, with the upmarket grocer recording an uplift from 4.2% to 4.5% while share at the German discounter increased from 2.4% to 2.9% and sales rocketed 25.2%.

Marks & Spencer, Lidl and Iceland also increased their share in the period, according to figures from Nielsen.

However, Tesco’s share slipped from 28.5% to 28.3% despite sales growth of 3.3% at the UK’s largest grocer.

Asda’s share also dropped year on year, from 16.4% to 16%. Sales grew 1.8%.

Morrisons share declined from 11.3% to 11% while sales were up 1.3%

Nielsen’s UK head of retailer and business insight Mike Watkins said: “Sainsbury’s continues to lead the top four supermarkets in terms of sales growths so their market share has increased over the last 12 weeks. Waitrose also grew share, to 4.5%. However, the fastest growing food retailer continues to be Aldi with a +25% increase in sales. With continued high levels of advertising, Aldi is one of the few retailers consistently able to attract significantly more new shoppers.”

Grocery sales by value among the UK’s leading supermarkets were up 2.8% in the four weeks to May 25 as volumes remained flat.

This compares with a 1.4% drop in value in the previous four weeks, when volumes slid 3%, affected by the timing of Easter.

Watkins said:  “The recent four-week reporting period was a tale of two halves. The first two weeks and the better weather saw strong growths, while the middle of May saw slowing growths compared with the same period in 2012 with its warm weather.

“Spend on offer fell to 33% of sales, and while this is still high, retailers are using multiple tactics to encourage shopper loyalty including couponing and vouchering, everyday low price and loyalty card initiatives, as well as
in-store promotions.”

 12 w.e 25/05/201312 w.e 26/05/2012% sales change