Diesel at £2 a Litre: What It Costs Your Fleet in 2026

On 2 October 2026 the average price of a litre of diesel in the UK reached 200.01p, according to the RAC. It is the first time the national average has gone over £2. The previous record, 199.09p, had stood since June 2022, and it fell on 28 September. A 55-litre tank now costs about £110.

For a household that is painful. For a fleet running thousands of litres a month, it changes the budget.

Why diesel has gone up so far

Two conflicts are pushing on the same product.

The Iran war. Since the war began in late February 2026, shipping through the Strait of Hormuz has been badly disrupted. Before the war, more than a fifth of the world’s oil trade passed through it. Brent crude closed at $104.28 a barrel on 8 October, and the US Energy Information Administration expects it to average about $105 in the last quarter of the year.

Russian refineries. Ukrainian drone strikes have cut output at half of Russia’s largest diesel-producing refineries. Russia’s diesel and gasoil exports fell to around 755,000 barrels a day in September, the lowest for the time of year since 2017, and Moscow has restricted fuel exports to protect its own supply. The UK stopped importing Russian oil products in 2023, but those missing barrels still have to be replaced from somewhere else, and that tightens the whole diesel market.

Diesel is hit harder than petrol because both shocks fall on middle distillates. The RAC’s figures show the gap: on 2 October petrol averaged 174.71p, more than 25p a litre below diesel.

Nobody can tell you when this ends. The RAC’s head of policy put it simply: only a sustained fall in oil prices brings pump prices down. Plan as though £2 is the price for a while.

What £2 a litre means for a van fleet

Take a fleet of 20 diesel vans, each covering 25,000 miles a year at 35 mpg. That is about 3,250 litres per van per year.

	Per van, per year	20 vans, per year
Litres used	3,247	64,944
Cost at 200p (inc. VAT)	£6,494	£129,888
Cost ex. VAT (if you reclaim it)	£5,412	£108,240
Every extra 1p a litre adds	£32	£649

Swap in your own mileage and mpg in the van fleet fuel cost calculator. Bunkered or fuel-card prices will differ from the pump average, but the shape of the sum does not.

And for an HGV

An artic covering 80,000 miles a year at 8 mpg uses roughly 45,500 litres. At the pump average that is about £91,000 a year including VAT, or around £75,800 ex. VAT, for one truck. Run the numbers for your own vehicles in the HGV fuel consumption calculator.

What a saving is now worth

At £1.40 a litre, a few per cent off the fuel bill is a nice extra. At £2 it is real money. On the 20-van fleet above, ex. VAT:

Fuel saved	Worth per year
1%	£1,082
5%	£5,412
10%	£10,824

The percentages are there to show the value of each point, not a promise. What your fleet saves depends on how fast your drivers go now and on which roads.

Where the fuel actually goes

Some of the fuel bill is fixed by the job: the miles, the load, the vehicle. A large part of it is set by how the vehicle is driven, and above about 45 to 50 mph the biggest single factor is speed. Aerodynamic drag rises with the square of speed, so the last few mph on a motorway cost far more fuel than the first.

That is why the cheapest place to start is the top of the speed range.

• Vans. The motorway limit for a van is 70 mph, but nothing in the van stops it doing 80. Many fleets set a lower cap, often in the low to mid 60s, and accept a few minutes on a long run in return for a lower fuel bill. Our guide to speed limiters for vans covers how fleets choose the figure.
• HGVs. Trucks over 7.5 tonnes are already limited to 56 mph by law, so the gains come from the driving below that: steady speeds, less harsh acceleration, less idling. Some operators set their limiters a little lower than the legal maximum.
• Idling and harsh driving. Telematics shows you where they happen. TrackSpeed combines a speed limiter with ScorpionTrack GNSS tracking, so you can see both the speed and where it happened.

Our fuel savings from speed limiters article goes through the published studies on speed and fuel use in more detail.

Things to do this month

1. Know your real cost per mile. Fuel cards and mileage give you litres per 100 miles by vehicle. Rank the fleet. The worst 10% of vehicles usually tells you more than the average.
2. Find the speed. If you have tracking, look at time spent above 65 mph by vehicle and by driver. If you do not, a sample of journeys will still show the pattern.
3. Set a speed policy and make it stick. A written policy depends on the driver. A sealed limiter holds the figure whoever is driving. The DBW speed limiter works on electronic-throttle vans and trucks and takes about 1.5 hours to fit.
4. Check tyres and loads. Under-inflated tyres and unnecessary weight both add fuel. They are quick wins while you sort the rest.
5. Work out the payback. The speed limiter ROI calculator shows how quickly a limiter pays for itself at today’s diesel price, which is faster than it was last year.

Frequently Asked Questions

Why is diesel more expensive than petrol right now?

Both the Iran war and the strikes on Russian refineries hit middle distillates, the part of the barrel that diesel comes from. Diesel supply is tighter than petrol supply, so the price gap has widened. On 2 October 2026 diesel averaged 200.01p and petrol 174.71p, according to the RAC.

Will diesel go back below £2?

That depends on oil prices. The RAC has said only a sustained fall in oil prices will bring pump prices down, and the US Energy Information Administration expects Brent to average around $105 a barrel in the fourth quarter of 2026. Budget for £2 until the market says otherwise.

How much does each penny on diesel cost my fleet?

Multiply your annual litres by £0.01. A van doing 25,000 miles a year at 35 mpg uses about 3,250 litres, so each 1p adds around £32 a year per van. For 20 vans, that is about £650 a year for every penny.

Does slowing down really save fuel?

Yes. Above roughly 45 to 50 mph, aerodynamic drag becomes the main load on the engine, and it rises with the square of speed. Taking the top off motorway speeds is one of the most direct ways to cut fuel use. How much you save depends on how fast your vehicles are driven now.

Is a speed limiter worth it with diesel this high?

The higher the fuel price, the faster any fuel saving pays back. Use the speed limiter ROI calculator with your own mileage and current speeds to see the figure for your fleet.

Talk to us about your fleet

Tell us what you run and how far it goes, and we will recommend the right limiter for each vehicle. Request a quote.