Cash-strapped drivers are still getting a “raw deal” at the pumps despite a record price drop last month, with many facing a "postcode lottery" when it comes to cheaper fuel.
Many supermarkets are cutting petrol and diesel prices, but the RAC motoring organisation found that what motorists pay varies hugely depending on where they are.
The RAC said average petrol prices sank to 169.8p per litre at the end of August – but they should be around 161p due to current wholesale costs.
The 12.3p drop in average prices was the largest monthly drop in records dating back 22 years. But the fall in wholesale costs means this “only tells part of the story”, the RAC said.
Spokesman Rod Dennis said: “12p a litre is a lot to come off prices in a single month so there’s no doubt things could be worse, but in reality drivers of petrol vehicles are still getting a raw deal at the pumps.
"For whatever reason, major retailers are choosing not to pass on in full the reductions in the wholesale price of unleaded they’ve been benefiting from for some considerable time now – and this continues to mean drivers are often paying much more every time they fill up than they should."
Dennis said many big supermarket petrol stations were close to 161p a litre, but that drivers faced a "real postcode lottery".
Drivers in some parts of the country face paying far more for fuel than others, including at supermarket forecourts where about 50% of motorists fill up.
The Mirror has approached Tesco, Sainsbury's, Morrisons, Asda and the Co-op for their average fuel prices.
Dennis added: "Drivers must shop around for the best deal they can, and we applaud those independent retailers who are doing their best to charge a fairer price for fuel and support their local communities through this incredibly expensive time."
A review by the Competition and Markets Authority found that growing oil refining margins were one of the main causes of fuel prices to soar earlier this year.
The increase from the crude oil price when it enters refineries to the wholesale price when it leaves them as petrol or diesel had more than tripled in 12 months to nearly 35p per litre.
