It claims a headline-grabbing ‘price war’ between supermarkets has seen pump prices fall — but not as fast as wholesale costs.
The organisation’s fuel spokesman Simon Williams confirmed: “The best advice for filling up is no longer to assume the supermarkets are the cheapest, but to shop around as it’s highly likely you’ll find an independent retailer which is doing the right thing and fairly reflecting their lower wholesale costs by charging a lower price.”
RAC Fuel Watch data revealed the wholesale cost of petrol delivered to forecourts fell for eight consecutive weeks by a whopping 20p from 151.93p at the start of June to 131.75p a litre in the last week of July.
The last time unleaded was this price on the wholesale market was in early May which a week later led to a UK average pump price of just 167p a litre.
Next was Texaco at the Chrysler Garage in Kettering at 171.9p.
Both were around a penny cheaper than latest supermarket prices at Morrisons, Asda, Tesco and Sainsbury in Kettering.
Tesco just seven miles down the A43 at Weston Favell and Morrisons in Wellingborough — less than six miles from Hannington — were both selling at a whole 10p dearer at 181.9p.
That equates to around £6 difference to fill up a family car.
Cheapest in Northampton on Tuesday was Esso's Abington Express in Wellingborough Road at 177.9p a litre. Best price in Corby was Asda at 177.7p.
Texaco Kettering, in Bayes Street, was also among the cheapest for diesel at 182.9p a litre on Tuesday.
Tesco at Weston Favell was asking 191.9p a litre.
Mr Williams added: “July has been an unnecessarily tough month for drivers due to the big four supermarkets’ unwillingness to cut their prices to a more a reasonable level, reflecting the consistent and significant reductions in the wholesale cost of petrol and diesel.
“As it was, we saw independent retailers leading the charge with fairer pump prices appearing all around the country which eventually forced the supermarkets to finally implement a more substantial cut late last Friday afternoon (July 29).
“What ought to have happened is that the biggest retailers cut their prices more significantly on a daily basis, given the wholesale price of petrol has fallen steadily over the last eight weeks. Instead, average retailer margin for petrol across the industry has been up around 20p a litre for the last two weeks – more than three times its long-term average.”
The RAC’s claims came on the same day BP reported its biggest quarterly profit for 14 years after oil and gas prices soared. The energy giant saw underlying profits hit £6.9 billion between April and June — more than triple the amount it made in the same period last year.