Diesel Prices Fall Record 17p in June 2026

UK diesel prices fell by a record 17p per litre in June 2026, the biggest monthly fall since records began in 2000, as a US-Iran peace deal sent the cost of oil tumbling. Petrol also fell sharply, dropping 8p per litre over the same month. However prices have since started rising again as fresh tensions emerged in July. Here is what happened, where prices stand now, and what drivers should expect next.

17p

Record monthly fall in diesel prices in June 2026 — biggest since 2000

167p

Average UK diesel price at end of June 2026, down from 184p at the start

$72.92

Brent crude price per barrel at end of June, down from $94.98 at the start

What caused the record price fall?

According to the RAC, the dramatic fall in fuel prices during June 2026 was driven by a deal between the US and Iran to end the conflict that had disrupted oil supplies through the Strait of Hormuz since late February. The peace deal caused the cost of a barrel of Brent crude oil to fall from $94.98 at the start of June to $72.92 by the end of the month — a fall of $22 per barrel in a single month. (source)

More tankers began passing through the Strait of Hormuz following the deal, meaning the physical supply disruption that had sent prices soaring began to ease. This caused oil prices to fall below pre-crisis levels for the first time since the war started on 28 February 2026.

The diesel price reduction was even greater at the big four supermarkets, where the average price came down 19p per litre — 3p more than the UK-wide average — from 182.37p to 163.28p per litre. Motorway services saw a smaller reduction, with diesel falling by around 14p and remaining above 187p per litre even at the end of June.

How does this compare to historical price moves?

The 17p monthly fall in diesel is significant in historical context. The RAC, which has tracked daily prices since 2000, confirmed this is the largest monthly fall it has recorded in more than 25 years. Petrol's 8p monthly fall was the seventh largest on record.

However, RAC head of policy Simon Williams cautioned against excessive optimism: "While diesel dropping 17p in a month is very positive, it's also important to realise that its average price shot up 49p a litre from the end of February to 191.54p on 15 April." Even after the record monthly fall, diesel remained around 25p per litre more expensive than before the conflict began in February 2026.

Where are prices now in July 2026?

The price falls did not last. Fresh escalation in tensions between the US and Iran in early July put upward pressure back on oil markets. According to Regit, drivers were paying an average of 151.0p per litre for petrol in early July, slightly higher than the six-week low of 150.7p recorded in late June. Diesel had risen from its June low of 164.8p to around 164.9p per litre. (source)

Luke Bosdet, the AA's fuel price spokesperson, said drivers could face further increases despite recent falls, with the geopolitical situation remaining uncertain. Russia's restrictions on fuel exports also added upward pressure on diesel specifically.

Our live price trends chart shows exactly how petrol and diesel prices have moved since we began collecting hourly data in April 2026, capturing both the spike caused by the conflict and the subsequent fall.

Which regions saw the biggest falls?

According to Regit, only Northern Ireland, the North East, and Yorkshire and the Humber had average petrol prices below 150p per litre as of early July. These regions, which were already among the cheapest in the UK before the conflict, benefited most from the June price falls in absolute terms.

Our regional prices page shows live average prices for every UK region, updated hourly. You can see exactly how your area compares to the national average right now.

Will prices fall further?

The outlook is uncertain. The peace deal that triggered June's record fall remains fragile, and any breakdown in US-Iran negotiations could send oil prices back towards the conflict-era highs of $120+ per barrel. At the same time, if the peace deal holds and Strait of Hormuz traffic returns fully to normal, there is room for further price falls.

Adding to the complexity, UK fuel duty rises from September 2026 will add approximately 1.2p per litre at the pump regardless of wholesale oil prices. By March 2027, the cumulative duty increase will add 6p per litre. See our September fuel duty guide for the full timeline.

How to take advantage of falling prices

When prices are falling, the difference between the cheapest and most expensive stations tends to widen, as some retailers are slower to pass on wholesale falls than others. This is the classic rocket and feather effect — prices rise fast but fall slowly, and different retailers fall at different rates.

Use our live fuel price map to find which stations near you have already passed on the price falls and which have not. Updated every hour from official Government Fuel Finder data, it shows you exactly which nearby station is cheapest right now — not last week's price.

Diesel Prices Fall Record 17p in June 2026 — What Happened?