The pump price of diesel should be 16p per litre cheaper than it currently is and fuel retailers are keeping the cost high despite a marked fall in wholesale prices, two of the UK’s biggest insurance firms have told Autocar.
According to data from RAC Fuel Watch, diesel is now 6p per litre cheaper than petrol on the wholesale market. However, diesel is currently 13p per litre more expensive on UK forecourts than petrol, at 159.43p versus 146.5p. That means filling a family car with a 55-litre tank – such as a Volkswagen Golf – with diesel costs £87.69 but filling the same car with petrol is £80.60.
Given the drop in wholesale prices, the RAC says drivers should be paying 143p for a litre of diesel.
The discrepancy in forecourt prices occurs despite the wholesale price of diesel remaining cheaper than petrol for the entire month of April – at 104.88p per litre – and a gradual drop in diesel prices over the past six months. The wholesale price of petrol dropped 6p per litre in April to 111.25p.
In Northern Ireland, the forecourt price of a litre of diesel averages 147.7p – 13p less than on UK forecourts as a whole.
The AA said: “This is an ongoing scandal that both the AA and RAC have been attacking for weeks. The fuel retailers say the added cost is needed to compensate for the poor return they get from supplying diesel under oil company contracts to businesses. The gap between pump price (minus tax) and wholesale is so big it renders that argument complete nonsense.”
RAC fuel spokesman Simon Williams added: “This just isn’t fair for the country’s 12 million diesel car drivers. We feel there should be an obligation on retailers to reflect wholesale price movements on their forecourts. Sadly, the only place this seems to happen is in Northern Ireland, where a litre of diesel is, incredibly, being sold for 12p less than the UK-wide average.
“Our data shows that the average retailer margin on a litre of diesel is a shocking 22p a litre compared to petrol, which is around 8p. The long-term averages for both fuels is 7p, which means retailers are making three times what they have in the past for diesel. This is hard for them to justify and equally hard for diesel drivers to swallow.”
At the end of April, the average price of unleaded was at 142.99p a litre at a major UK supermarket – 3.5p cheaper than the UK average. Diesel was being sold at 156.68p, which is 2.75p cheaper than the average and 3p down since the start of the month.
A spokesman for the British Retail Consortium said: “The price of diesel has been falling consistently throughout 2023 as retailers aim to provide their customers with the best value for money.”