Diesel Reaches Two Pounds a Litre: What It Costs You Now

The sequel nobody wanted has arrived. The average price of a litre of diesel in the UK crossed £2 on Friday for the first time ever, hitting 200.01p according to RAC data, breaking the previous record of 199.09p set back in June 2022. Petrol averaged 174.71p the same day. We wrote in our September piece about diesel edging towards the threshold and what it would mean if it crossed; now it has, and the running-cost maths against electric has shifted again.

How we got here

The route from ordinary prices to £2-a-litre diesel runs through the US-Iran war that began in late February. The RAC's numbers make the speed of it plain: diesel averaged 142.38p at the start of the conflict, so it is up 57.6p a litre in just over seven months. Petrol has risen 41.9p over the same period. Prices hit a new record on Monday and kept climbing through the week, and the RAC's head of policy Simon Williams said the rise was "showing no signs of slowing". The supply disruption behind the surge is still running, which is the risk sitting on top of the price already at the pump.

For a household, the increase lands in the tank. Filling an average 55-litre family diesel now costs about £110, roughly £32 more than it did at the end of February. The equivalent petrol fill is £96, up £23. Drivers who cover big miles feel it first, and Williams pointed out the irony that diesel cars, long the default recommendation for high-mileage drivers, are now the ones burning a hole in pockets.

The record also matters beyond the pump. Williams warned that businesses may have no option but to pass the additional costs onto customers, naming haulage and delivery firms, fleet operators and sole traders, which is how a fuel price becomes an inflation problem for everyone. The previous high had stood for more than four years: the 199.09p record of June 2022 was set in the wake of Russia's invasion of Ukraine, and it has taken a second supply shock, this time centred on the Gulf, to break it.

Where the money goes

A pound a litre is a useful checkpoint for asking what a litre actually costs, because a large slice of the £2 never reaches an oil company. Analysis by the RAC Foundation of government Fuel Finder data shows that 86p of the £2 litre of diesel, 43%, goes to the Treasury in fuel duty and VAT. Fuel duty is frozen at 52.95p per litre, and VAT is charged on both the fuel and the duty, so tax rises in cash terms as prices climb. Petrol carries an even heavier proportion: 82p of its 174.7p, or 47%. Steve Gooding, the Foundation's director, called the £2 mark psychological and pointed out that most drivers have no choice about whether to make a journey. The scale of the exposure is large: there are 10.3 million diesel cars and a further 4.6 million diesel vans on UK roads, every one of them paying the record price.

What it costs per mile

This is where the figure becomes useful for anyone weighing up their next car. The RAC estimates that an average diesel doing 45mpg now costs about 20p per mile in fuel alone, so a 10,000-mile year works out at roughly £2,020. The arithmetic behind that is easy to picture: a 45mpg car covers roughly ten miles on a litre, so each 200p litre spreads across about ten miles. Stretch the same maths to a high-mileage driver covering 15,000 miles a year and the fuel bill approaches £3,030. That is fuel only: servicing, insurance and depreciation sit on top.

We will not pretend the electric comparison is simple, because it is not. Home charging on a smart tariff costs a fraction of that per mile, public rapid charging costs considerably more than home charging, and the spread between the two is wide, as our price cap coverage set out at the start of the month. What the diesel record does is move the worst case for petrol and diesel running costs far enough up that the whole electric range, from cheap home charging to expensive motorway rapid charging, now sits below it on fuel alone. A driver who cannot charge at home and pays premium public rates is still likely to spend less per mile than a 45mpg diesel does at today's prices. That is the practical meaning of a £2 litre.

What it means for the market

There is early evidence that fuel prices are pushing buyers rather than just annoying them. The SMMT's chief executive Mike Hawes said this week, alongside September's record registration figures, that high fuel prices are "undoubtedly giving more consumers reason to consider going electric". September's market, where battery electric cars took a record 28.3% share and plug-in hybrids another 17.0%, is consistent with that reading, though model choice and discounts deserve much of the credit too.

The RAC is calling on the government to respond, asking for a further fuel duty cut or a VAT reduction in the Budget, and Williams noted that households squeezed by rising energy bills are facing all of this at once. Whether the Chancellor moves is unknowable from here. What we can say is that the £2 threshold, once a hypothetical we wrote about with some care in September, is now the average, and the running-cost argument that used to need a spreadsheet now makes itself at the pump.

How we got here

Where the money goes

What it costs per mile

What it means for the market

Sources