Aldi and Asda have seen their market share fall according to fresh data from analysts NIQ.

Asda’s share plummeted to 11.8% in the 12 weeks to 7 September, from 13.1% a year ago. Meanwhile, Aldi’s share also slipped from 10.7% to 10.3% over the same period.

The decline of Asda tallies with rival analyst Kantar’s data, which found that its share had fallen 1.2 percentage points to 12.6% in the 12 weeks to 1 September.

It follows as Lord Rose, who the grocer revealed today would take over from Mohsin Issa in the day to day running of Asda, last month said he was “embarrassed” by its performance.

Elsewhere, Ocado retained its crown as the fastest growing retailer with sales up 15.4% over the past 12 weeks, followed by M&S, which had a 12.4% jump.

Morrisons also increased spend per visit following additional More Card offers and Waitrose attracted more shoppers and visit compared to last year.

Supermarkets as a whole saw till sales dip over the past month, with the slowdown likely due to cooler weather and a return to regular routines for shoppers following the summer break, according to NIQ.

Total till sales fell from 5.5% the prior month to 4% in the last four weeks ended 7 September, the NIQ reported.

NIQ UK head of retailer and business insight Mike Watkins said: “September is closely tied to a change in how we shop following ‘back-to-school’, so retailers typically reinvigorate marketing efforts as customers refocus on new routines as we go from summer to autumn.

“With some 50% of households saying they are moderately or severely impacted by the increases in cost of living, this means retailers will need to be laser-focused in offering products and promotions that inspire customers who are budget-conscious as part of the push for sales growth in Q4.”

He added: “Many households are now budgeting for Christmas and slowly stocking their cupboards to help spread the cost.

“So whilst promotions are still key, assessing the impact of all media spend is more important as this helps retailers and brands get a better understanding of shopper behaviour and purchasing drivers.”

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