UK drivers are paying sharply more at the pumps after petrol and diesel prices each rose by about 5p per litre in a week.
RAC Fuel Watch put the UK average at 167.17p per litre for unleaded and 188.63p for diesel on 9 September 2026. That weekly increase adds about £2.75 to a 55-litre fill, before any further movement at individual forecourts.
Fuel Finder UK’s own later snapshot showed the same direction. At 15:03 on 9 September, accepted reports from the government’s statutory fuel-price feed produced an equal-site average of 167.6p for petrol and 189.1p for diesel. On that measure, a 55-litre fill was about £92.18 for petrol or £104.01 for diesel.
What has happened to UK fuel prices?
The RAC reported that both fuels had risen by 5p per litre over seven days. Fuel Finder’s UK Fuel Price Index also showed substantial weekly increases across thousands of reporting forecourts.
The two organisations’ national averages differ slightly because they use different methods and observation times. Fuel Finder gives every eligible forecourt equal weight and excludes reports that fail its freshness or data-quality checks. The RAC produces its own national market measure. Both datasets point to the same conclusion: the cost of filling up increased quickly during the first part of September.
Why did petrol and diesel rise so quickly?
Crude oil moved back above $100 a barrel as renewed attacks involving the United States and Iran increased concerns about disruption to global supplies. Brent settled at $101.21 on 9 September, according to Associated Press market reporting.
Higher crude prices do not pass through to every forecourt immediately or by the same amount. UK pump prices also depend on refined-fuel costs, the pound-to-dollar exchange rate, distribution costs, retailer pricing and tax. The RAC said oil had averaged about $96 a barrel over the previous week and that higher wholesale costs were already feeding through to forecourt prices.
How much difference does shopping around make?
National averages are useful for tracking the market, but they are not the price every driver will pay. Fuel Finder’s 9 September index snapshot put supermarket petrol at 163.3p per litre, compared with 169.8p across BP, Shell and Esso branded sites in the same dataset.
That measured 6.5p gap is worth about £3.58 on a 55-litre fill. It is a group comparison rather than a guarantee that every supermarket is cheaper, so checking the stations along your actual route remains more useful than choosing by brand alone.
- Compare nearby forecourts before setting off. A short detour may save money, but a long diversion can use more fuel than it saves.
- Check when the price was reported. Fuel Finder displays reported prices, and a forecourt can change its price after submitting an update.
- Avoid motorway filling where practical. Plan a stop near your route before joining a motorway or major trunk road.
- Drive smoothly. Gentle acceleration, sensible speeds and correctly inflated tyres can reduce fuel use.
Will fuel prices keep rising?
There is a clear risk of further increases if crude and wholesale fuel prices remain elevated. It is not yet possible to say how large any further rise will be, or whether today’s oil price will persist long enough to reach UK forecourts in full.
Oil markets can reverse quickly as supply expectations and geopolitical events change. Treat precise pump-price forecasts with caution. The most reliable view for an individual journey remains the latest reported price at nearby stations.
The bottom line
The 5p weekly rise is real and is already costing a typical driver around £2.75 more for a 55-litre fill. Diesel remains considerably more expensive than petrol, while the spread between nearby forecourts means there is still money to be saved by comparing before filling up.
Use Fuel Finder UK to compare the latest reported prices near you, or follow the Fuel Price Pulse for a consistent weekly view of the market.
Sources and methodology
- RAC: Fuel prices spike, 9 September 2026
- Associated Press: Oil rises above $100, 9 September 2026
- Fuel Finder UK press data and methodology, snapshot to 9 September 2026 at 15:03
- Fuel Finder UK Fuel Price Index, 9 September 2026 snapshot
Fuel Finder figures are unweighted averages of the latest accepted reported price at each eligible forecourt. Each site counts once, regardless of sales volume. Figures are snapshots of reported prices, not a guarantee of the price available when a driver arrives.