If you fill up a 50-litre tank at 140p a litre, you hand the cashier £70. Only about a third of that actually pays for the fuel. The rest is tax, duty, a refinery’s margin, a wholesaler’s cut, a retailer’s slice, and a handful of pence for the forecourt itself to keep the lights on. Pump price is the last number in a long chain — and understanding the chain is the difference between feeling gouged and knowing what to expect.
What you’re actually paying for
A typical pence-per-litre breakdown on UK unleaded at 140p looks roughly like this:
- Wholesale cost — around 55-60p. The rack price the retailer pays for the refined fuel, delivered to their site. Moves daily with crude oil and sterling.
- Fuel duty — 52.95p. A fixed flat rate per litre, set by the Treasury. Frozen since March 2011 and currently kept at a temporary 5p reduction. Doesn’t change with the pump price.
- VAT — 23.33p. Twenty percent of everything above (wholesale + duty + retailer margin). You pay tax on top of the tax.
- Retailer margin — 6-9p. What the forecourt actually keeps. Covers staff, rent, card fees, maintenance, and profit. Thinner than most drivers assume.
The headline: roughly 55% of what you pay is tax. Fuel duty plus VAT add up to about 76p of every 140p litre. The government’s share dwarfs the forecourt’s. When the Chancellor announces a “fuel duty freeze,” it matters.
Why the pump price moves
Duty and VAT are flat — the moving parts are wholesale and margin. Wholesale tracks three things daily:
- Brent crude — the global benchmark. A $5 move in crude pushes the rack price by about 3p/L, depending on sterling.
- The pound against the dollar — crude is priced in dollars. A weaker pound means imported fuel costs more in sterling, even if the crude price is flat.
- Refinery and logistics margins — outages, maintenance, shipping disruptions (Red Sea, Rotterdam strikes) all filter through within days.
Retailers watch the rack price every morning and adjust their forecourts accordingly — though not always the same day. Theretailer lag between a wholesale drop and the pump catching up is typically 5-10 days. When wholesale rises, forecourts tend to pass it on faster.
Why the station down the road is different
Two forecourts on the same road can differ by 10p or more. The reasons are prosaic:
- Different wholesale deals — supermarkets buy on annual contracts in bulk; independent stations pay spot prices.
- Different rent bills — a London forecourt has very different property costs from a rural one.
- Different competition — a station with three rivals within a mile prices tighter than one with none.
- Different timing — some retailers reprice at 6am, others at midnight; a station that hasn’t caught up to yesterday’s wholesale drop will be a penny dearer for a few hours.
What drivers can do
You can’t control duty, VAT, crude or sterling. You can control where and when you fill up. Three levers:
- Compare, always — the gap between cheapest and dearest within a five-mile radius is often 10p. On a full tank that’s a £5 difference for two minutes of checking.
- Time it — Tuesday mornings are historically the cheapest slot of the week (see our piece on the weekly rhythm), and a forecast engine can flag when the trend is about to flip.
- Use loyalty properly — supermarket points and fuel cashbacks knock 2-3p off effective price, if you pick the right card for each forecourt brand.
None of this is rocket science. The reason most drivers still overpay is that the information has been invisible — price boards you glimpse at 50mph, no way to see the whole market at once. That’s the gap FuelHawk fills.
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