The cheapest supermarket for fuel prices, revealed

Supermarkets are charging up to 14p more for fuel on some forecourts, according to a survey by the RAC.

The average price of a litre of unleaded stayed at 140.5p in January while diesel remained at 148.5p, putting the cost of full tanks at £77.24 and £81.73p respectively.

However, RAC analysis of the prices charged by the big four supermarkets that dominate UK fuel retailing via the government’s voluntary price reporting scheme, found “wildly different” prices are being charged from place to place.

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On 31 January there was 14p difference between the cheapest supermarket fuel and the most expensive.

The cheapest litre of unleaded found by the RAC was sold by Sainsbury’s (SBRY.L) for 131.9p in Oxford and Newport, with the most expensive being Morrisons at 145.9p in Exeter and Ipswich.

It is a similar tale with diesel prices, with supermarket prices varying widely depending on location.

Some retailers bucked the trend and sold fuel at a far lower rate, including Costco (COST), which charged drivers £1.30 for diesel and 139.6p for diesel, although this is only available to members.

Similarly, independent forecourt Grindley Brook in Whitchurch, Shropshire, was charging just 133.9p for petrol – nearly 7p less than the UK average, forcing nearby retailers to drop their prices.

RAC fuel spokesman Simon Williams said: “While petrol is at its lowest point for well over two years, January unfortunately brought an end to three consecutive months of falling prices at the pumps.

“It is still concerning to see that fuel remains considerably cheaper in Northern Ireland and that the supermarkets are charging wildly different prices for identical petrol and diesel at different locations around the UK.

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“The data retailers are voluntarily providing to the Competition and Markets Authority has shed a whole new light on the pump price postcode lottery. It seems blatantly wrong to us that the very same petrol or diesel can vary in price by as much as 14p a litre, depending on where drivers are filling up."

In Northern Ireland, petrol was 4.2p cheaper than the UK average at 136.2p by the end of the month and diesel was 3.5p lower at 144.9p, showing drivers are still not being charged a fair price across the whole of the country.

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