Why Fuel Prices Fall Slower Than They Rise

Most drivers have noticed it: when oil prices jump, pump prices follow within days. When oil falls, pump prices seem to take weeks to come down. Economists call this the "rockets and feathers" effect.

What is happening?

Retailers buy fuel in advance and hold stock. When wholesale prices rise, stations tend to raise pump prices quickly to protect their margin on the next delivery. When wholesale prices fall, some stations hold prices higher for longer, which widens their margin.

Part of the delay is genuine: fuel already in the tank was bought at the old price. But the effect is also linked to how much competition there is nearby. Where drivers have few choices, prices can stay high for longer.

What has the regulator said?

The Competition and Markets Authority (CMA) has monitored UK fuel markets for years. In the 2026 price rise, reports say the CMA found no sign that retailers were exploiting the crisis, but warned that some had been slow to pass on falls in wholesale prices. It has said it plans a closer look this autumn. Check the CMA's own publications for the latest, as our summary is not the official position.

Prices can also drop fast when conditions change. Reports said diesel fell by about 17p a litre in a single month in June 2026 when hopes of peace lifted oil markets.

What it means for your wallet

• Price falls are not shared equally. Some stations pass them on quickly and others do not. That is why the gap between cheapest and dearest is so big. In our data it was over 50p a litre on E10 on 6 November.
• The national average hides the best deals. When oil falls, the cheapest stations in your area will drop first. The dearest may barely move.

How to catch falls early

1. Check prices after a news event. If oil has fallen sharply, compare local stations again within a few days.
2. Compare, don't assume. The station that was cheapest last month may no longer be. Search your postcode to see current prices and when each last changed.
3. Hold off on a full tank if prices are falling and you have fuel to spare, but never let the tank run dry to wait for a saving.
4. Follow the trend. Our guide on what affects the price of petrol and diesel explains which numbers to watch.

Better data makes it harder to hide

The government's Fuel Finder scheme requires stations to report price changes quickly. That makes it easier for drivers, and regulators, to see which stations are slow to cut prices.

The takeaway

Falling prices reach the cheapest stations first. The way to benefit is to look, not to wait. Find the cheapest fuel near you.

Compare prices in your city: London, Birmingham, Manchester, Leeds, Glasgow, or see petrol prices by city.