The ‘myRAC Fuel Finder’ app shows drivers the cheapest fuel prices across the country and could save diesel drivers up to 6p a litre and petrol drivers up to 5p per litre.

In June, the price of unleaded petrol rose by 0.7p, to 143.9p, while the cost of diesel fell by 1.2p to 145.46p.

This is the first time in eight months the price of petrol has risen and the eight-month diesel prices have been falling.

Yet the RAC says on average retailers are making a margin of 12p a litre for petrol and 13p a litre for diesel, compared to the long-term margin of 7p.

It comes after a report from the Competitions and Markets Authority (CMA) found that supermarkets have been overcharging drivers for fuel. In 2022, drivers lost out on these savings by around £900 on average.

Following the report, the Government has announced the launch of a new comparison website to help drivers to easily compare fuel costs in real time.

Yet the RAC says its app is already providing this service with its fuel finder tool, launched this week. The savings available for drivers who use the app are equivalent to £3.30 for diesel drivers filling up a 55-litre tank and £2.75 for petrol drivers or £172 and £143 a year respectively.

Drivers are able to make five searches a day for local fuel prices and they can choose a two, five, or 10-mile radius from their chosen location.

They are then be shown the five cheapest places to buy fuel near them. They can then compare these prices to the UK average. Drivers can also set up alerts in the app for their MOT, tax, and car insurance renewal dates.

‘Prices should be 5p lower for petrol and 6p for diesel’

The RAC says the big four supermarkets have been slow to pass on wholesale savings. This was also illustrated in this week’s CMA report.

It is now warning drivers not to automatically assume that they will get the cheapest price from a supermarket forecourt.

Geographically, prices vary considerably across the country, despite retailers paying the same amount for wholesale fuel. In June, for example, petrol was 4p a litre cheaper and diesel was 7p a litre cheaper in Northern Ireland when compared to Great Britain.

RAC fuel spokesman, Simon Williams, said: “June marked the end of the price of petrol falling at the pumps, purely because retailers are taking more margin per litre than they used to. Looking at the wholesale price of both petrol and diesel which is almost identical, average forecourt prices should be 5p lower for petrol and 6p for diesel.

“The myRAC app can help drivers save up to 6p a litre compared to the average prices in most areas. And savings can often be far greater than that, particularly with diesel which has been overpriced on so many of the country’s forecourts this year due to its wholesale price being lower than petrol’s for the last three months, with many retailers sadly not passing this on to their customers.

“The more people who seek out the lowest prices using it, the more likely we are to see other retailers nearby lower their prices to compete. And, as we know, proper competition is often lacking in UK fuel retailing everywhere but in Northern Ireland where prices are considerably cheaper than on the other side of the Irish Sea.”