Fuel prices go up by 2p a litre as supermarkets hike their prices over and above the wholesale market increase

The price of fuel rose by 2p a litre in December as a result of three of the UK’s major supermarkets putting up their prices well above the increase seen on the wholesale market, data from RAC Fuel Watch shows.*

The average price of petrol went up from 114.39p to 116.46p (2.07p) and diesel from 117.72p to 120p (2.28p) over the course of the month. On the wholesale market a litre of unleaded went up by just 1.28p from 85.76p to 87.04p. Diesel rose by 1.11p from 88.33p to 89.44p. Looking at wholesale prices from two weeks ago – the time it takes for all retailers to replenish their stock, the RAC believes drivers should in fact be paying around 113p for petrol and 118p for diesel.

Of the four big supermarkets fuel retailers however, Morrisons, Sainsbury and Tesco all raised their forecourt prices by an average of 3p a litre, with only Asda matching the wholesale market price increase by raising its prices by around 1.5p a litre.

This meant that Asda was selling both the cheapest supermarket petrol and diesel at the close of December. A litre of unleaded cost 110.11p a litre (up 1.31p from 108.8p) and diesel 113.4p (up 1.52p from 111.88p). Sainsburys was 1.5p dearer for petrol and 1.38p for diesel. Despite this, filling up at a supermarket is still 4p a litre cheaper for unleaded and nearly 4.5p for diesel.

The cost of filling a 55-litre tank of fuel for a family petrol car rose by £1.14 from £62.91 to £64.05, and by £1.25 from £64.75 to £66 for diesel. Refuelling at a supermarket currently saves drivers over £2 a tank.

RAC fuel spokesman Simon Williams said:

“It’s very disappointing to see some of our biggest fuel retailers putting up their prices over and above the increases seen on the wholesale market. There’s a definite feeling that they have been trying to protect themselves for what was to come in terms of further coronavirus restrictions.

“While wholesale prices went up very slightly in December our data shows there should be scope to lower forecourt prices rather than put them up. Retailers will no doubt argue that the pandemic is leading to drivers filling up far less so their ‘per litre’ profits are considerably down, and Monday’s announcement of another lockdown will be treated as justification for their decision not to pass savings on at the pumps. Unfortunately, those who still need to fill up regularly are having to pay more than they should be as, by our calculations, both fuels should actually come down by 3p a litre in the next fortnight.

“That said, the oil market is still being adversely impacted by Covid travel restrictions so it may be the case that drivers are paying less for their fuel than they might otherwise be. And, even though a barrel of oil was above $50 for half of December – something that we haven’t seen since March last year – the wholesale price didn’t shoot up due to the pound gaining 2% on the dollar.

“Interestingly, retailers have adjusted their margins and are now making roughly the same on petrol as diesel whereas normally they take a larger margin on a litre of diesel. For example, in September the margin on diesel was 4.5p more than petrol at an average of nearly 11.5p (11.4p) a litre compared to around 7p (6.85p).

“As and when life begins to become more normal as a result of the Covid vaccination programme the price we pay for fuel will inevitably go back up again. A year ago, a litre of unleaded set drivers back 127p and diesel 132p, which is 10p and 12p more expensive, respectively, than today.”

Regional pump prices compared

Find out more about UK petrol and diesel prices on the RAC website.