It found the biggest price difference for the basket was at Morrisons Daily, where shoppers paid 21 per cent more on average for the same groceries than at a full-size Morrisons s

New research shows that shoppers buying essentials including milk in store from Tesco, Sainsbury's and Morrisons are paying more in convenience stores than in the larger outlets

An investigation has found that Tesco, Morrisons and Sainsbury's all charged more for a basket of shopping in their smaller local convenience stores.

The biggest different was at Morrisons Daily, where shoppers paid 21 per cent more on average. Which? found that Sainsbury's and Tesco had less variation in prices, but Nectar mem

The biggest different was at Morrisons Daily, where shoppers paid 21 per cent more on average. Which? found that Sainsbury's and Tesco had less variation in prices, but Nectar members could still be paying an average of 14 per cent more at Sainsbury's Local.