Petrol retailers failed to pass on wholesale price savings to UK customers last month, and instead increased their share from forecourt costs last month, according to data from RAC Fuel Watch.
The motoring group revealed the average price of petrol fell by only 2p a litre despite wholesale prices dropping around the festive season, meaning UK drivers collectively paid £156m – over £5m a day – more for petrol than they should have.
Instead of taking the established margin of 6p a litre, retailers gobbled up an average of 16p a litre on petrol and 12.5p on diesel in December.
RAC reported that unleaded petrol dropped from 147.47p a litre to 145.48p, when drivers could have seen prices nearer to 135p had retailers not changed their pricing strategy,
Diesel also dropped by just under 2p a litre from 150.80p to 148.92p when drivers should have been paying around 142p.
This means it has cost petrol car drivers £6 more to fill up a typical 55-litre family car than it should have (£80 v £74), and for diesel nearly £4 more with a tank costing £82 at the end of the month instead of £78.
RAC fuel spokesman Simon Williams said: “December was a rotten month for drivers as they were taken advantage of by retailers who rewrote their pump price strategy, costing motorists millions of pounds as a result.”
He argued petrol retailers have “taken advantage of all the media talk about ‘higher energy prices’ and banked on the oil price rising again and catching up with their artificially inflated prices.”
Williams urged ministers to put pressure on petrol sellers to lower costs as “the Treasury’s coffers have been substantially boosted on the back of the retailers’ action.”
“The trouble is every extra penny they take as margin leads to drivers paying even more as VAT gets added on top at the end of the forecourt transaction. This means the Treasury’s coffers have been substantially boosted on the back of the retailers’ action. We urge ministers to push retailers into doing the right thing for consumers.
Supermarkets account for over a third of UK petrol forecourts and around half the UK’s market share.
RAC revealed Asda had the cheapest petrol at the end of the year with a litre costing an average of 141.81p at their stores, with Sainsbury’s not far behind at 142.57p.
Asda also sold the lowest priced diesel at 144.9p a litre ahead of Tesco on 145.8p.
The average price of motorway unleaded at the close of December was 160.55p while diesel was higher still at 163.43p.
This is not the first time motoring groups have criticised petrol retailers, with RAC warning fuel sellers to not to exacerbate last winter’s crisis as prices soared to record highs.
A spokesperson for the British Retail Consortium said: “Supermarkets are keen to provide their customers with the best value for petrol through their forecourts, offering the cheapest petrol in the country. However, prices at the pump will be influenced by various forces, including tax, oil prices and operational costs.”