Tesco may be twice as powerful as previously thought - as the dominant retailer in 67 per cent of UK postcodes, according to a new study.
The survey shows that Tesco controls the market in 81 of the 121 UK postcodes.
This local share is more than double its national share at 31 per cent because of the number of stores in areas such as Truro and Swansea, according to retail consultancy CACI.
