UK supermarket inflation rose to 2.6 per cent in June, up from 2.4 per cent in May, as shoppers faced higher prices across fish, chocolate and fresh fruit.

The increase marked the first monthly rise in more than a year, according to consumer group Which?, which monitored more than 27,000 grocery products.

Fish recorded the sharpest category increase, with prices rising 11.1 per cent compared with June 2025. Energy drinks followed at 5.5 per cent, while chocolate rose 3.8 per cent, water increased 3.6 per cent and fresh fruit climbed 3.4 per cent.

However, Which?’s longer-term measure showed annual inflation across the three months to June slowing to 2.8 per cent, down from 3.1 per cent in the three months to May.

Tesco recorded the highest single-month inflation rate among the supermarkets monitored at 4.1 per cent, followed by Sainsbury’s at 3.9 per cent and Waitrose at 3.5 per cent. Aldi’s prices declined by 0.1 per cent, although Which? noted that inflation measures the speed of price changes and does not indicate which retailer is cheapest.

“After months of easing grocery inflation, this month’s increase is a reminder that pressure on household budgets hasn’t disappeared,” Which? retail expert Reena Sewraz said.

Among individual products, Asda’s Just Essentials Mild Cheddar Slices recorded the largest increase. The average price of a 200g 10-pack rose from 65p in the three months to June 2025 to £1.39 during the equivalent period this year, representing a 113 per cent rise.

A 750ml bottle of Shloer Zero White Grape at Asda increased by 95 per cent, from £1.42 to £2.77.

Other notable rises included Sainsbury’s own-label pork pies, up 92 per cent; a 40g bag of Kettle crisps at Morrisons, up 70 per cent; and a 350g pack of breaded haddock fillets at Tesco, up 54 per cent, The Independent reported.

Tesco disputed the figures and said Which? had not shared its calculations with the retailer.

Sainsbury’s argued that the products highlighted were not representative of a typical weekly shop, while Asda pointed to independent surveys that it said regularly demonstrated its price competitiveness.

Which? called on supermarkets to maintain the availability of affordable budget ranges across their store estates as cost pressures continued to affect household spending.

Its full supermarket inflation tracker monitors prices at eight major grocery retailers.

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