Sainsbury's overtakes Asda to become UK's second-biggest supermarket

Sainsbury's has overtaken Asda to become the UK's second-biggest supermarket for the first time in a decade, according to research group Nielsen.

The latest data caps an impressive run of 35 consecutive quarters of growth for Sainsbury's, while Asda by comparison has struggled to keep up with its lack of convenience stores and being tainted by the horsemeat scandal.

Sainsbury's market share rose from 16.4 per cent to 16.6 per cent in the 12 weeks to 13 October compared with the same period a year earlier, while Asda dropped from 16.7 per cent to 16.4 per cent.

Asda has been number two, behind Tesco, since 2003 as Sainsbury's struggled with lacklustre stores and was consistently beaten on price by its rivals.

The shift has also happened because Nielsen, which is the world's largest research agency, recently changed the way it reports supermarket share to make it more accurate.

Bosses at Sainsbury's had been suggesting privately that they had overtaken Asda since the start of the year, but online, convenience and non-food sales had not been taken into consideration as heavily in previous Nielsen data.

Tesco's market share also slipped during the period from 30.1 per cent to 29.5 per cent.