Why Is Petrol So Expensive? How UK Fuel Prices Actually Work

You've probably stood at the pump, watching the numbers spin past £50, then £60, then £70, and thought: "Where is all this money actually going?" You're not alone. It's probably the most common question I get asked, right after "should I buy diesel?"

The honest answer is that the price you pay for fuel is only partly about the actual fuel. The rest? That's a story involving global politics, government tax policy, supermarket strategy, and a hefty dose of "because they can." Let me break it down properly.

What You're Actually Paying For

Let's say you're paying around 140p per litre for unleaded. Most people assume that money goes straight to Shell or BP or whoever's logo is on the forecourt. Not even close.

Here's roughly where every pound you spend on fuel ends up:

• Fuel duty: around 30% - A flat rate the government charges on every single litre sold in the UK, before anything else gets added.
• VAT: around 20% - Charged on top of everything, including the duty (yes, really, more on that in a minute).
• Wholesale oil cost: 25-30% - The actual cost of crude oil on international markets, which gets refined into the petrol or diesel in your tank.
• Refining and transport: 10-15% - Turning crude oil into usable fuel and getting it from the refinery to your local forecourt isn't free.
• Retailer margin: 5-10% - What the actual petrol station keeps. This is often the thinnest slice of the lot.

So roughly half of what you pay at the pump is tax. The actual petrol? That's barely a quarter of your total bill. Once you understand that split, the whole pricing picture starts making a lot more sense.

The Oil Price Connection

You'll hear people say "oil prices have gone up" every time fuel gets more expensive. And they're not wrong but the relationship isn't as straightforward as you'd think.

Crude oil is traded globally in US dollars. So the price you eventually pay at a UK pump depends on two things: what oil costs on international markets, and what the pound is worth against the dollar. If oil stays flat but the pound weakens, your fuel still gets more expensive. It's a double whammy that catches people out.

Then there's the delay factor. The oil being refined into fuel today was probably bought weeks ago. Refineries don't work on a "today's price" basis instead they buy in bulk, on contracts, at varying rates. So when you see headlines about oil dropping by 10%, don't expect that to show up at your local pump by Tuesday afternoon.

If you want to keep tabs on how these shifts actually play out at UK forecourts, our fuel price trends page tracks the real numbers over time, not just the headlines. The GOV.UK fuel price statistics are also worth a look if you want the official historical data.

That said, wholesale costs do filter through eventually. It just takes longer than you'd like, which brings us to something called the "rocket and feather" effect later on.

Why Fuel Duty Is the Elephant in the Room

Here's where it gets properly frustrating. Fuel duty in the UK is a fixed amount per litre currently frozen at a rate that's been held for years. You can check the exact current rate on the GOV.UK fuel duty rates page.

That duty gets added to every litre regardless of whether oil is cheap or expensive. So even if global oil prices halved overnight, you'd still be paying the same duty. It acts as a floor price - fuel in the UK can never really be "cheap" because of it.

But here's the real kicker that winds people up: VAT is charged on top of the duty. Read that again. You're paying a tax on a tax. The government adds duty to the fuel, then charges you 20% VAT on the whole lot including the duty they just added. It's like being charged a booking fee on a service charge. Madness, but that's how it works.

This is why UK fuel prices are so much higher than in countries like the US. Americans pay a fraction of the tax we do. Their fuel is fundamentally the same stuff but it's the tax structure that creates the gap.

Every few years there's talk of cutting fuel duty or reforming how VAT applies. Sometimes there's even a temporary reduction. But the underlying structure hasn't fundamentally changed in a long time, and I wouldn't hold your breath waiting for it to.

The Supermarket Effect

Ever noticed that the cheapest fuel near you is almost always at a supermarket? That's not a coincidence, no, it's a deliberate business strategy.

Tesco, Asda, Sainsbury's, and Morrisons don't make much money on fuel. Sometimes they barely break even on it. They use cheap fuel to get you through the door, or, more accurately, onto their car park because once you've filled up, there's a solid chance you'll nip in for a pint of milk, a meal deal, and somehow leave with £40 worth of shopping you didn't plan on buying.

Fuel is what's called a "loss leader." The supermarkets can afford to sell it at razor-thin margins because they make their profit inside the shop, not on the forecourt. Independent stations and branded forecourts like Shell or BP can't compete with that model because fuel is their actual business. They need that margin to keep the lights on.

This creates some interesting regional patterns. If you live near several supermarkets, competition keeps prices keen. If you're in a rural area with one independent station and the nearest Tesco is twenty miles away, you're probably paying noticeably more. Our UK market insights section covers some of these regional differences in more detail.

The practical takeaway? Don't just fill up at whichever station you happen to pass first. A few minutes comparing prices locally can save you a surprising amount over a year.

Why Prices Go Up Fast but Come Down Slowly

This one drives everyone mad, and rightly so. When oil prices spike, the pump price seems to jump overnight. But when oil comes back down, prices at the forecourt drift lower at what feels like a glacial pace.

There's actually a name for this: the "rocket and feather" effect. Prices rocket up quickly but float down like a feather. And it's not just your imagination as studies have consistently confirmed this pattern exists in UK fuel markets.

Why does it happen? A few reasons. Retailers buy fuel in advance, so they genuinely are selling stock they paid more for even after wholesale prices drop. But there's also an element of "because they can." When prices are rising, no one notices if a station adds an extra penny because everyone expects it. When prices are falling, every penny they hold onto is pure profit. It's not a conspiracy, it's just business incentive working exactly as you'd expect.

This is where tracking tools become genuinely useful. RAC Fuel Watch does a solid job of monitoring average prices and calling out when retailers are being slow to pass on savings. Keeping an eye on the trend yourself means you can time your fill-ups a bit smarter rather than just accepting whatever's on the board when your light comes on.

What You Can Actually Do About It

Right, so you can't control oil prices, you can't change fuel duty, and you're not going to single-handedly reform VAT policy. But there are practical things that genuinely make a difference.

Compare prices locally. This is the single biggest thing. Prices between stations just a mile or two apart can vary by 5-10p per litre. On a 50-litre tank, that's up to a fiver every time you fill up. Use our live fuel map to check what's cheapest near you before you set off.

Don't fill up on motorways. Motorway services are consistently the most expensive places to buy fuel in the UK. Plan ahead and fill up before you hit the motorway, or come off at a junction near a supermarket. The difference can be 15-20p per litre - that's not small change.

Think about your driving style. Harsh acceleration, heavy braking, and sitting in the wrong gear all burn more fuel than you'd think. Smooth, steady driving in the right gear can improve your fuel economy by 10-15% without any mechanical changes. The AA fuel advice page has some decent tips on this if you want to dig deeper.

Consider the bigger picture. Fuel costs are just one part of what it costs to run a car. Insurance, servicing, depreciation, and tax all add up. Sometimes a car that's slightly less efficient but cheaper to insure and service actually costs less overall. Our running costs guides help you see the full picture rather than just fixating on miles per gallon.

Look at what you're driving. If you're doing serious mileage, the difference between a car doing 40mpg and one doing 55mpg is hundreds of pounds a year. Which? cars has independent economy test results that are worth checking before your next purchase. And browse our guides for more advice on choosing a car that fits your budget and lifestyle.

Time your fill-ups. Prices tend to be lowest mid-week at supermarkets and highest over bank holiday weekends when demand spikes. It's not a massive difference, but combined with everything else, it adds up.

Dave's Take

Here's the blunt truth: fuel in the UK is expensive primarily because the government takes a massive cut. Around half of what you pay is tax, and that's not changing any time soon, regardless of what any politician promises at election time.

The oil market adds volatility on top, and retailers aren't exactly in a rush to pass savings on. That's the reality. Getting angry about it is understandable, but it doesn't save you money.

What does save you money is being a bit smarter about where you fill up, how you drive, and whether you're in the right car for your needs. None of it is complicated, it just takes a bit of awareness. The people who pay the most for fuel are the ones who never think about it at all.

You can't beat the system, but you can stop letting it take the mick.