Supermarkets and several other retailers are failing to reduce petrol prices in line with falling wholesale costs, the RAC has warned.
RAC Fuel Watch data shows petrol fell by 8.4p last month to 151.06p making a full 55-litre tank for a family car £4.63 cheaper (£83.08). Diesel came down by 9.4p to 173.97p meaning a complete fill-up was £5.19 less than it was at the start of the month at £95.68.
But the motoring group said petrol prices should actually be around the UK for 140p – 11p less than the current UK average. For diesel drivers the figure should be nearer to 160p a litre – 14p lower than the average at the end of 2022.
Unleaded bought at one of the big four supermarkets reduced by 10p a litre from an average of 157.86p to 147.76p and diesel by 11.4p from 181.66p to 170.23p.
“On the face of it, December looks like it was a good month for drivers with 9p coming off at the pumps on top of November’s 6p, but there’s no question that the drop should have been far bigger given how far wholesale prices have come down,” RAC fuel spokesman Simon Williams said.
“For weeks we’ve been calling on the big four supermarkets to cut their prices more substantially to give drivers a fairer deal when they fill up, so even though they have reduced their prices collectively by more than 10p a litre in December, they are still nowhere near where they should be given the scale of the drop in wholesale prices. We hope the Business Secretary’s intervention just before Christmas puts more pressure on larger retailers to do the right thing,” he added.
RAC noted that membership-only retailer Costco, which “consistently charges some of the lowest prices in the UK”, is currently charging a store-wide average of 137.3p for unleaded and 158.4p for diesel which means members can save £7.50 on a tank of petrol (£75.51) and £8.50 for diesel (£87.17).
Williams also highlighted the case of Northern Ireland, where fuel prices are significantly cheaper.
“Looking at prices in Northern Ireland is a good reference for what should be happening across the rest of the UK as petrol was 4.5p cheaper there than the UK average at the start of December but was nearly 7p lower at the end of the month at just 144.43p. For diesel the difference is even more pronounced as a litre was 7p cheaper at the beginning of December and 9.5p less by the close at 164.55p,” he said.
“If fuel can be sold this cheaply in Northern Ireland, then this must mean something is very wrong with fuel retailing in mainland UK,” he added.