Total Till sales at UK supermarkets slowed to 7.2% in the four weeks to 12 August, the lowest level since January.
The latest data from NIQ found the drop in sales came as a result of lower inflation, as well as unsettled, unseasonable weather over the summer months as shoppers visited stores fewer times.
To encourage consumer spending and ease the effects of the cost-of-living crisis, retailers have further increased spend on promotional activity by 23%, up 0.5% from the month prior, on all FMCG goods.
This comes on top of targeted price cuts by most UK supermarkets and the use of loyaty cards to assist with savings.
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NIQ found that Tesco saw an increase in sales by 9.7% and gained market share over the last 12 weeks, while M&S, Aldi and Lidl were the only other retailers to gain market share in the period.
This comes as 62% of consumers continue to shop at discounters, which have attracted over 780,000 new shoppers compared to this time last year.
However, Morrisons and Co-op were found to be the retailers with the weakest growth up just 1.7% and 2%, respectively.
NIQ UK head of retailer and business insight, Mike Watkins, said: “Recent weeks have seen a decline in supermarket volumes, likely influenced by factors such as summer holidays and unpredictable weather.
“It’s evident that encouraging consumer spending has become an industry challenge, extending beyond just grocery shopping.
“With the added concerns of increasing mortgage and rental expenses for many households, it appears that a shift in sentiment may be some time off and as a result, while total till growth will continue to decelerate as inflation eases, it will still be difficult for retailers and manufacturers to drive FMCG volume growths”.
