Diesel at 199.33p: why the South feels the squeeze, and the tax rules drivers should know

Diesel is now within a whisker of £2 a litre. According to the RAC, the average UK price has hit 199.33p, with petrol also climbing. When a BBC News report on people across the South asked "what can we do?", it was putting a question that many drivers have been muttering at the pump for weeks.

Most coverage stops at the pump price. This piece looks at what sits underneath it: how much of that price is tax, what you can legitimately claim back if you drive for work, and which tempting shortcuts could land you in serious trouble.

What happened

The RAC reported that UK diesel reached 199.33p per litre. The report attributed the surge to the continuing Middle East conflict and said diesel has risen by almost 40% since the conflict began. Petrol has risen too, but diesel has taken the harder hit.

The BBC's focus on the South is worth noting. The region is often assumed to be comfortable, but that glosses over the drivers who depend on a vehicle most: people in rural and coastal areas, shift workers, carers, tradespeople and anyone whose nearest bus is infrequent or non-existent. The BBC report is about their reaction. The reasoning below is my own analysis rather than anything the report says.

Why it matters

Diesel is the fuel behind the shelves

Diesel is not just a private motorist's problem. Vans, lorries, delivery fleets, taxis and many agricultural vehicles run on it. When diesel jumps, businesses face higher running costs, and some of that can end up in the price of goods and services. Even if you drive a petrol car or an EV, you may still feel it indirectly.

The commute does not flex

A lot of fuel spending is non-discretionary. You can skip a weekend drive, but you cannot easily skip the school run, the hospital appointment or the 25-mile trip to work when the alternative is a once-an-hour bus. That is why the "what can we do?" question lands so hard in less densely served areas.

Tax takes a bigger bite as prices rise

Pump prices include fuel duty and then VAT on top of everything, duty included. Two things follow from that:

• VAT is a percentage. At 199.33p, one-sixth of the price is VAT, which works out at roughly 33p per litre. As the pump price rises, the VAT take per litre rises with it, even though the rate has not changed.
• Duty is a fixed amount per litre. The main rate has been 52.95p per litre for both petrol and diesel since March 2023. Duty does not rise with the wholesale price, but it is the same on diesel and petrol, so it does not explain why diesel has pulled ahead.

If that duty rate still applies when you read this, duty plus VAT adds up to something like 86p of every litre at today's price. Check GOV.UK for the current rate, as it can change with Budget decisions.

That does not mean the government is the main driver of the latest spike. The RAC attributes that to the conflict. But it explains why calls for tax relief tend to follow every price surge, and why any change to duty or VAT would be felt immediately at the pump.

The legal and tax angle

This is general information, not legal or tax advice. Where your income or liability is at stake, speak to an accountant or check the official guidance.

If you drive for work, check what you can claim

At nearly £2 a litre, it is worth knowing the rules:

• Commuting is generally not claimable. Travel from home to a permanent workplace is treated as ordinary commuting for tax purposes.
• Employees using their own car for business trips. Employers can pay tax-free mileage under HMRC's Approved Mileage Allowance Payments (AMAP). The rates are 45p per mile for the first 10,000 business miles in a tax year and 25p per mile after that for cars and vans. The rate is flat and does not move with the pump price, so a high diesel price effectively squeezes the real-terms value of the allowance.
• Company car drivers. If your employer pays for fuel and you use the car privately, or you pay for fuel yourself and claim business miles back, HMRC's Advisory Fuel Rates apply. These are per-mile rates by engine size and fuel type, and HMRC reviews them regularly. If you are reimbursed at a stale rate while prices spike, it is reasonable to ask your employer which rate they are using and whether it has been updated.
• Self-employed drivers. Most sole traders can choose between claiming actual vehicle costs or using simplified mileage rates, and the choice has consequences for other claims. With fuel this expensive, it is worth running the numbers properly, ideally with an accountant.
• VAT-registered businesses. VAT on fuel can be reclaimed for the business portion, subject to the usual rules. Private use complicates things, so keep good mileage records.

Whatever your situation, keep receipts and a mileage log. Fuel costs are one of the easiest things to under-evidence and one of the first things an enquiry looks at.

The red diesel trap

When diesel hits £2, rebated "red" diesel starts to look tempting. It is lawful for certain off-road and specified uses, but using it in a road vehicle is generally an offence. HMRC can impose penalties and seize vehicles, and fuel can be tested during roadside checks. The saving is never worth that risk. If you are unsure whether you are entitled to use rebated fuel for a particular machine, check GOV.UK or ask your supplier.

Pump accuracy and pricing

When you pay for fuel, what you are charged should match what was delivered and what was advertised. Pump measuring equipment is subject to weights and measures legislation enforced by local Trading Standards. If you think a pump has shorted you, or the forecourt price differs from the price charged, keep your receipt and raise it with the retailer, then with Trading Standards if needed.

The government's Fuel Finder scheme, which requires forecourts to share price data, is aimed at making comparison easier. For more on whether it is likely to bring prices down, see our post on whether Fuel Finder will make UK pump prices fall.

Driving off without paying

Forgetting to pay is common when drivers are rattled by the total. Making off without payment is a criminal offence under the Theft Act 1978, and the "I forgot" defence depends on honest intent. If you realise your mistake, go back or call the forecourt promptly. Our piece on drive-off petrol thefts rising as fuel prices jump covers how forecourts are responding.

What drivers should know

Do the sums on the "cheaper fuel" trip

A 12-mile detour to save 6p a litre rarely pays. Work out the fuel you burn getting there, then compare it with the saving on a typical fill. For many people the nearest decent-value forecourt on their usual route will beat the cheapest one across town.

Watch for the parking trap at the forecourt

Chasing cheap fuel can lead you into private forecourts and retail sites with their own rules. Queueing on a forecourt, stopping at a supermarket petrol station to shop, or staying beyond a posted limit can attract a private parking charge. For how these charges work, see our guide to Euro Car Parks petrol queue fines and your rights.

Cut the avoidable use

These are the practical basics, and they work:

• Check tyre pressures. Under-inflated tyres increase rolling resistance.
• Take unneeded weight out of the boot. Roof boxes and bike racks add drag when empty.
• Smooth your driving. Gentle acceleration and anticipating traffic burn less than late braking and harsh throttle.
• Combine errands. One longer trip with a warm engine uses less fuel than several cold starts.
• Plan around congestion. Idling in traffic is wasted diesel.

For more on speed and economy, see our post on the 60mph rule and cutting fuel costs.

Think twice about the "do nothing" shortcuts

Don't skip servicing or ignore warning lights to save money. A clogged diesel particulate filter or a faulty injector can cost far more than the fuel you were trying to save, and it can also create an MOT problem.

Review your wider driving costs

If a diesel car is a daily necessity for you, look at the whole picture: insurance renewal, breakdown cover, and whether car-sharing or a park-and-ride makes sense for some trips. If you are weighing up a switch to electric, our post on what rising petrol prices mean for UK EV interest looks at the demand side.

Looking ahead

Nobody can say with confidence where pump prices go from here. The RAC links the surge to the Middle East conflict, which means the path depends largely on events outside UK control. Pump prices also tend to lag wholesale moves, as we explored in our post on why petrol savings are slow to reach drivers. Even if wholesale costs ease, relief at the forecourt may take time to show.

Three things are worth watching:

1. Fuel duty decisions. Ministers have repeatedly faced the choice between holding duty down and protecting revenue. Any change to the 52.95p rate or its planned path will matter more when prices are this high. For the latest position, see our post on fuel duty rises and what drivers face.
2. Competition scrutiny. The Competition and Markets Authority has been looking at fuel pricing. Whether that leads to meaningful change is an open question.
3. Business knock-on effects. If haulage and delivery costs stay high, expect the conversation to broaden from "what can drivers do?" to "what are shops and suppliers passing on?"

The bottom line

The BBC's question, "what can we do?", has no single answer. But there are sensible, lawful steps. Keep good records if you drive for work. Check that your employer's mileage rates are current. Do not be lured by rebated fuel. Plan fuel stops so you do not trade a few pence for a parking charge. And keep an eye on tax announcements, because with duty and VAT making up a large slice of every litre, policy decisions will shape what you pay as much as events overseas.

This article is general information about UK motoring rules and is not legal or tax advice. For your own circumstances, consult HMRC guidance on GOV.UK or a qualified adviser.