Asda's share of the clothing and footwear market rose to 9.4% in the three months ending July 25. During the same period, M&S held a 9.1% share of the market, according to figures from the FashionTrak survey, compiled by Taylor Nelson Sofres.
The news is being hailed as a success for Asda's George label, founded in 1990, and is more bad news for Stuart Rose, the beleaguered chief executive of M&S.
M&S has been taking steps to shore up its declining clothing sales by introducing new ranges such as Per Una, which is designed to appeal to younger and more fashion-conscious women. The M&S brand was once a staple in the lives of British women but has been accused of falling behind the times.
In contrast, Asda has eschewed the high fashion route for a policy of offering quality clothes at value prices. Asda has opened five standalone George stores and the clothes are sold in parent company Wal-Mart's shops in Germany, Korea, Japan, Mexico, Canada and the US.
Rose has promised M&S shareholders that he will turn around sales at the company and has already outlined a plan to buy the Per Una label from its creator, George Davies. It has already dropped the David Beckham childrenswear range DB07.
The decision was made after Philip Green, the owner of the rival Arcadia fashion group, made a bid for M&S.
FashionTrak also showed that Arcadia's Dorothy Perkins and Top Man stores managed to increase their share of the market while its Top Shop, Evans, Burton and Bhs chains all lost share.
Tesco, which has started advertising its clothing range on television, increased its share of the clothing market, as did Next and Matalan.
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