Owners of diesel cars are paying up to 8p per litre more than necessary as filling stations fail to pass on savings in wholesale costs.
The latest figures from RAC Fuel Watch show that the wholesale price of diesel has been lower than that of petrol for six weeks but retailers have maintained forecourt prices well above that of unleaded.
A litre of diesel costs 3.5p more than a litre of petrol, on average, despite the wholesale price being 2p per litre cheaper. Throughout September, on average, a litre of diesel cost 118p while a litre of unleaded was 114p.
The RAC argues that retailers could be charging 110p per litre for diesel and still obtain a 5p per litre margin, compared with the 11p per litre margin they are currently taking.
Simon Williams, RAC fuel spokesman, said that diesel drivers had a right to feel short-changed by retailers who were keeping diesel prices artificially high.
Fuel prices remained virtually unchanged during September after three months of increases. Petrol was down 0.17ppl while diesel was down 0.3ppl. The latest figures show that petrol is nearly 9p per litre more expensive and diesel 7p more than the record lows during lockdown but both are significantly cheaper than they were at the start of the year. An average fill-up of either is around £7 cheaper than in January.
Simon Williams commented: “After three months of rising fuel prices drivers will be relieved to see the cost of both petrol and diesel staying the same. Since June when prices stopped falling as a result of the coronavirus movement restrictions being eased, the cost of fuel has been going up steadily. While price rises are never good news, they have not gone back to the high levels seen at the beginning of the year.
“Despite this, diesel drivers should feel short-changed by the decision of retailers to keep prices artificially high. The price of a litre is currently 8p higher than it should be due to reductions in the wholesale price. In fact, the wholesale price of diesel has now been lower than the petrol equivalent for six weeks, yet petrol continues to be sold for 3.5p less than diesel. This must surely be difficult for retailers to justify. We strongly urge them to lower their prices in an effort to restore drivers’ trust.”
He added that recent drops in oil prices, higher production rates and a reduction in demand as the holiday season draws to an end could all contribute to lowering prices at forecourts in coming weeks.