The UK's Competition and Markets Authority (CMA) has announced it will intensify its monitoring of petrol and diesel prices nationwide. Fuel retailers responsible for thousands of stations have been put on notice that they must hand over revenue, cost, and sales data sooner than originally planned.
The move comes as global oil markets remain volatile following the escalating conflict in the Middle East, with pump prices rising sharply in recent weeks. The CMA wants to ensure that any price increases at the forecourt genuinely reflect wholesale cost pressures — and that drivers are not being overcharged.
What the CMA is doing
The CMA has used its statutory powers to issue formal information notices to major fuel retailers, requiring them to supply detailed data on revenues, costs, and sales volumes. This data collection has been brought forward — ahead of the watchdog's normal reporting schedule — to allow faster analysis of what has happened to margins since the current Middle East conflict began pushing oil prices higher.
Once the data is in, the CMA will examine two key questions: whether fuel margins have widened during the current period of volatility, and whether there is evidence of so-called "rocket and feather" pricing — where pump prices rise quickly when wholesale costs go up, but fall far more slowly when costs come down.
"Whilst price increases might be inevitable because of rising wholesale costs, it is important that those increases reflect genuine cost pressures. We will be closely scrutinising and reporting on what's happening with fuel prices and call out any concerning behaviour."
— Juliette Enser, Executive Director for Markets, CMA
The CMA has made clear that it does not set or approve fuel prices — retailers are free to price as they wish. But the watchdog will publish its findings publicly, naming any behaviour it considers unfair or exploitative.
Why this matters now
Fuel prices have been climbing since late February 2026 following the escalation of tensions in the Middle East. Brent crude oil surged above $85 per barrel after Iran announced restrictions on shipping through the Strait of Hormuz — a route through which roughly a fifth of the world's oil supply passes daily.
The impact has fed through to UK pumps quickly, with petrol rising by several pence per litre in a matter of weeks. As of mid-March 2026, average unleaded stands at around 139p per litre, with diesel at approximately 157p per litre. Both are significantly higher than they were at the start of the year.
For drivers, the concern is not just that prices are rising — but whether they are rising by more than they should, and whether they will come back down fairly when wholesale costs ease.
What is "rocket and feather" pricing?
"Rocket and feather" describes a pattern where fuel retailers pass on wholesale price increases to drivers almost immediately, but are much slower to reduce prices when wholesale costs fall. The price goes up like a rocket, but comes down like a feather.
This has been a recurring concern in the UK fuel market. The CMA's own research found evidence of rocket and feather pricing in diesel during 2022, and the pattern has been flagged repeatedly by motoring organisations since.
In its most recent annual report (December 2025), the CMA highlighted a telling example: wholesale petrol costs had fallen by more than 7p per litre over several weeks, but the average pump price had dropped by less than 1p over the same period. The AA described this as a textbook case of the pattern.
What to watch for
If oil prices settle or fall in the coming weeks but your local station keeps prices high, that's a sign of delayed pass-through. Comparing prices regularly helps you spot stations that adjust fairly — and avoid those that don't.
Fuel margins: the story so far
The CMA has been monitoring fuel retailer margins since its major market study in 2023, which concluded that competition in the UK road fuel market had weakened significantly.
The findings have been consistent: margins remain well above historic norms, and the gap cannot be explained by rising operating costs alone.
The CMA's December 2025 annual report found that petrol retail spreads — the gap between what retailers pay for fuel and what they sell it for — averaged 15.4p per litre, more than double the 6.5p average seen during 2015–19. Diesel spreads were even wider at 18.8p per litre, compared with the 2015–19 average of 8.6p.
On a margin basis, supermarket retailers were averaging around 9.6p per litre, while non-supermarket forecourts averaged 11.1p per litre — both well above the levels seen in the years before the pandemic.
Importantly, the CMA found that operating profit margins for large fuel retailers were increasing, not decreasing — which directly challenges claims by some in the industry that higher pump prices are being driven by rising costs.
How transparency is improving
The CMA's stepped-up monitoring comes alongside broader changes to how fuel pricing works in the UK, giving drivers more power than ever to compare and choose.
July 2023 — CMA market study published
The CMA concluded that competition in UK road fuel had weakened, with margins rising. It recommended a fuel finder scheme and ongoing monitoring.
June 2025 — Data (Use and Access) Act receives Royal Assent
Gave the government legal powers to require fuel stations to report prices publicly.
February 2026 — Fuel Finder goes live
All UK petrol stations must now report price changes within 30 minutes. Data feeds into comparison tools, mapping apps, and sat-navs.
December 2025 — CMA annual report
Found margins remained "persistently high" and that operating costs did not explain the increase.
March 2026 — CMA accelerates monitoring
Formal data requests brought forward to investigate pricing behaviour during the current conflict-driven price spike.
The Fuel Finder scheme, which went live in February 2026, now requires every UK petrol station to report price changes to a central database within 30 minutes. This gives comparison tools — and the CMA itself — access to near-real-time pricing data from over 8,000 forecourts.
Retailers that fail to comply can face penalties of up to 1% of worldwide turnover, with additional daily fines of up to 5% of daily worldwide turnover for ongoing breaches. The CMA has said that its initial focus has been on helping businesses comply, but enforcement action will follow where necessary.
What this means for drivers
The CMA's intervention doesn't change prices directly — but it does increase pressure on retailers to price fairly, and it means any evidence of exploitation will be made public.
For drivers, the practical takeaway remains the same: fuel prices vary significantly between stations, and comparing before you fill up is one of the simplest ways to avoid overpaying. The difference between the cheapest and most expensive station in any given area can easily be 10–20p per litre — and during volatile periods like the current one, those gaps can widen further.
What you can do
- Compare prices before filling up — use a fuel comparison tool to check what stations near you are charging right now.
- Watch for slow price drops — if oil prices fall but your local station stays high, try a competitor.
- Avoid motorway services — they consistently charge 15–30p more per litre than nearby towns.
- Track your regular stations — monitoring prices over time helps you spot which stations adjust fairly.
- Use loyalty schemes — supermarket fuel cards can shave a few extra pence per litre.
With both the CMA and the Fuel Finder scheme now providing greater scrutiny and transparency, drivers have more tools than ever to hold fuel retailers accountable — simply by choosing where to fill up.