Grocery price inflation rose in September, with average supermarket prices climbing by 2%, according to industry data.

Prices were rising fastest in chilled soft drinks, chocolate confectionery and skincare, according to data from analysts Kantar.

The cost of some items fell, with the average price paid for toilet and kitchen roll 6% lower year-on-year, and dog and cat food 4% and 3% cheaper respectively.

Supermarket prices are now 2% more expensive than a year ago, up from August’s 1.7%.

Households responded by sending sales of promoted items up by 7.4% over the month while full price sales rose by just 0.3%. Overall take-home sales across the grocers rose by 2% over the same period.

Fraser McKevitt, head of retail and consumer insight at Kantar, said: “In the fiercely competitive retail sector, the battle for value is on.

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“Supermarkets are doing what they can to keep costs down for consumers and thanks to their efforts the prices in some categories are falling.”

September's weather, marked by persistent rain, contributed to notable spikes in sales for comforting products. Hot chocolate sales surged by 28%, soup sales increased by 10%, and home baking items saw a 7% rise. In a seasonal twist, Halloween pumpkin sales nearly doubled compared to the previous year, amounting to just under ￡1m over the last four weeks.

However, as consumers grapple with the cost of living crisis, a growing number of UK households are struggling to balance environmental concerns with financial pressures. Kantar’s survey revealed that 59% of Britons find it more challenging to act sustainably, a significant increase from 44% last year.

In market share developments, Tesco (TSCO.L) reported its largest share since December 2017, claiming 28% of the market, up from 27.4% a year earlier. Meanwhile, Asda’s sales fell by 5.1%, leaving it with a 12.6% market share. Morrisons, on the other hand, experienced a 2.8% sales increase, maintaining an 8.6% share.

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Ocado (OCDO.L) continued its streak as the fastest-growing grocer for the eighth consecutive month, boasting a 10% sales increase over the past 12 weeks. Lidl also performed well, with an 8.8% rise in spending, increasing its market share by 0.5 percentage points to 8.1%. Aldi accounted for 9.8% of total grocery spending.

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