UK Diesel Price May 2026: National Average and How It Compares
TL;DR: UK average diesel price was 145.7p/litre on 5 May 2026 (RAC Fuel Watch), down 1.5p over the prior month. Supermarket diesel averaged 141.5p; motorway service stations averaged 164.2p. Diesel sits at a 7.3p/litre premium over unleaded petrol, around the historical average. Fuel duty on diesel remains 52.95p/litre, frozen since March 2022.
UK Diesel Price by Retailer Type (May 2026)
| Retailer type | Average diesel (p/litre) | vs UK average | Source |
|---|---|---|---|
| Asda | 141.2p | -4.5p | RAC Fuel Watch |
| Tesco | 141.6p | -4.1p | RAC Fuel Watch |
| Sainsbury's | 141.7p | -4.0p | RAC Fuel Watch |
| Morrisons | 141.4p | -4.3p | RAC Fuel Watch |
| BP | 148.9p | +3.2p | RAC Fuel Watch |
| Shell | 148.5p | +2.8p | RAC Fuel Watch |
| Esso | 147.2p | +1.5p | RAC Fuel Watch |
| Motorway services | 164.2p | +18.5p | RAC Fuel Watch |
Prices verified via RAC Fuel Watch weekly retail data, 5 May 2026. Individual sites within each chain vary; figures are national averages weighted by transaction volume.
Why Diesel Prices Move Differently from Petrol
Diesel and unleaded petrol share the same fuel duty rate (52.95p/litre) and VAT treatment, so price differences arise primarily from wholesale costs and refining margins. Wholesale diesel pricing reflects distillate demand from heating oil, road freight, agriculture, and shipping, all of which increase northern hemisphere winter demand and are weaker in summer.
The May 2026 diesel premium of 7.3p over unleaded petrol is consistent with historical averages of 5-9p over 2018-2024. The premium widened to 30p in early 2022 following Russian export disruption (Russia historically supplied 10% of EU distillate) but has normalised as refining capacity adjusted and trade flows rerouted.
Regional Diesel Pricing in the UK
Regional variation in May 2026 diesel pricing follows similar patterns to petrol: Northern Ireland cheapest (140-142p average), East Midlands and Yorkshire next cheapest (143-144p), London and South East slightly above national average (146-148p), Highlands and Islands highest (149-152p). Motorway service stations everywhere price 15-20p above local non-motorway averages.
The Competition and Markets Authority (CMA) reported in its July 2024 fuel market study that supermarket retail margins on diesel averaged 8.4p/litre, up from 5-6p historically, suggesting reduced retail competition. The CMA's monitoring continues; a fuel finder service for consumer use is scheduled for 2026 implementation.
Fuel Duty and Tax Components on Diesel
For a diesel pump price of 145.7p, the approximate breakdown is: wholesale cost 53p; fuel duty 52.95p (frozen rate); VAT at 20% on (wholesale + duty + margins) approximately 24.3p; retailer and distributor margins 15-16p. The combined tax (fuel duty + VAT) totals approximately 77.25p, or 53% of the pump price.
HM Treasury fuel duty receipts for 2024-25 were £25.0 billion (HMRC fuel duty bulletin, 2025). The OBR projected fuel duty receipts of £25.6 billion for 2026-27 (Economic and Fiscal Outlook, March 2026), with the temporary 5p cut continuing.
FAQ: UK Diesel Price May 2026
What is the current UK average diesel price?
RAC Fuel Watch reported a UK average diesel price of 145.7p/litre for the week ending 5 May 2026. Supermarket diesel averaged 141.5p; motorway service stations averaged 164.2p. Northern Ireland averaged the cheapest regional pricing at 140-142p.
Will diesel prices rise or fall through summer 2026?
Forward markets price Brent crude in the $72-75/barrel range through Q3 2026. Absent geopolitical shock, this implies diesel pump prices may stabilise or decline marginally through June-August 2026. Summer demand for distillate is typically lower than winter, which could ease wholesale prices further.
Why is diesel cheaper at supermarkets than at branded forecourts?
Supermarkets use fuel as a customer footfall driver into stores and operate on lower retail margins (8-9p in 2024) compared to branded forecourts (12-15p). Supermarket sites are also typically larger volume per pump, allowing fixed costs to be spread across higher throughput.
Last reviewed: May 2026. Prices verified via RAC Fuel Watch 5 May 2026 weekly data; CMA fuel market study findings July 2024; HMRC fuel duty bulletin 2025; OBR Economic and Fiscal Outlook March 2026.
Refinery disruption and the October 2026 price picture
Refinery disruption and the October 2026 price picture
Renewed disruption to Russian refining capacity pushed wholesale oil higher in late August 2026, a move that feeds into UK pump prices with a short lag. The increase lands in the same week Ofgem confirms the October energy price cap, due by 26 August 2026. The current July to September cap is £1,663 a year for a typical direct debit household on the updated consumption basis.
Wholesale oil moved higher after fresh disruption to Russian refining capacity, according to data from the Office for National Statistics. The change in wholesale markets is expected to filter through to forecourt prices in the coming weeks, as retailers adjust to the new cost of supply.
UK pump prices track wholesale crude and product prices with a short lag. This means the recent upward movement in wholesale costs is not yet fully reflected in the prices drivers see at the pump, but the direction of travel points to higher costs ahead.
October energy price cap confirmation
Ofgem confirms the 1 October to 31 December 2026 energy price cap by 26 August 2026. The announcement will set the maximum rates for default tariffs, giving households clarity on their energy bills for the final quarter of the year.
The current July to September 2026 cap is £1,663 a year for a typical direct debit household on the updated TDCV basis. This figure represents the annual cost for a household with typical consumption paying by direct debit, and it forms the baseline against which the October cap will be measured.
Electricity VAT suspension
Electricity VAT is suspended to 0% from 1 October 2026 to 31 March 2027. The temporary reduction removes the standard 5% rate on electricity bills for six months, providing a further reduction in household energy costs during the winter period.
The suspension applies to electricity only and runs for a defined period, after which the standard rate is due to return. Households on all payment methods, including prepayment and standard credit, will see the reduction applied to their electricity charges.
What this means for household budgets
The combination of higher wholesale oil prices and the upcoming energy price cap announcement creates a mixed picture for household budgets. While petrol and diesel costs are likely to rise in the short term, the electricity VAT suspension offers some offsetting relief on energy bills from October.
Drivers filling up in the coming weeks should expect to see gradual increases at the pump as the wholesale price movements work through the supply chain. The full effect of the Russian refining disruption on UK prices will become clearer once the lagged adjustment is complete.
For households, the key dates to watch are the Ofgem announcement on 26 August 2026, which will set the October cap, and the start of the VAT suspension on 1 October 2026. Both events will shape the cost of living picture for the final quarter of the year.
- Renewed disruption to Russian refining capacity pushed wholesale oil higher in late August 2026.
- UK pump prices track wholesale crude and product prices with a short lag.
- Ofgem confirms the 1 October to 31 December 2026 energy price cap by 26 August 2026.
- The current July to September 2026 cap is £1,663 a year for a typical direct debit household (updated TDCV basis).
- Electricity VAT is suspended to 0% from 1 October 2026 to 31 March 2027.
Update: 11 September 2026 Fuel prices have risen sharply, with the average cost of unleaded petrol climbing 5p a litre in a week to 167.17p, according to RAC Fuel Watch. That is the biggest weekly increase since April and the highest price since September 2022. Diesel also rose 5p, reaching 188.63p a litre. The 5p rise adds about 2.75 pounds to the cost of filling a 55 litre family car. Brent crude returned to 100 dollars a barrel for the first time since July and averaged 96 dollars over the past week. Prices have risen since the US and Israel conflict with Iran began at the end of February, disrupting crude supply across the Middle East. US forces struck Iranian tankers and Houthi forces attacked Saudi oil facilities this week. RAC senior policy officer Rod Dennis said drivers are having to dig ever deeper and there is no sign of relief yet, with wholesale price rises already feeding through to forecourts. |
Update: 12 September 2026 UK average pump prices stood at 168.46p a litre for petrol and 190.08p for diesel on 11 September 2026, according to the RAC, which expects diesel to set a new high for the US/Iran war within days. The conflict's previous diesel peak was 191.54p on 15 April 2026, while petrol at 168.46p is the highest since September 2022. Wholesale oil rose about $6 overnight to nearly $108 a barrel, having averaged $96 over the preceding week. Both fuels are up 7p a litre since the start of September, adding £3.85 to filling a typical family-sized car. Diesel is rising about 0.77p a litre a day, the fastest rate since the conflict began, and is 33.5% more expensive than at the outbreak of war on 28 February 2026. RAC senior policy officer Rod Dennis said drivers are digging ever deeper at every fill-up with no sign of relief yet. Supermarkets average about 4p less than the UK average, around 164p petrol and 186p diesel, while some independent forecourts are under 158p for petrol. |
Fuel Finder enforcement and what drives pump prices now Fuel Finder has been live since 2 February 2026 under the Motor Fuel Price (Open Data) Regulations 2025. Every UK forecourt must report any pump price change to a central government database within 30 minutes, and must report registration details such as address, opening hours and fuels sold. Prices must be reported separately for each grade sold, including E5, E10, diesel, super diesel, B10 and HVO. The scheme is run by appointed aggregator VE3 Global for the Department for Energy Security and Net Zero, with the CMA responsible for enforcement. There is no official government Fuel Finder app; the data is published openly and feeds third party comparison sites, mapping apps and in-car navigation. The CMA ran a grace period to the end of April 2026 and began prioritising enforcement action from 1 May 2026, having written to forecourt operators on 2 April 2026. In its August 2026 road fuel monitoring report the CMA said it had sent 1,166 letters to retailers and issued compliance notices in respect of 53 sites since the grace period ended. The CMA has imposed no financial penalties to date, and VE3 had not referred any suspected breach of the price reporting duty to the CMA at the time of that report. The CMA linked its stepped up monitoring of petrol and diesel prices to the effect of the conflict in the Middle East on pump prices and retailer margins. Fuel Finder came out of the CMA's 2023 road fuel market study, which found that competition at the pump was not working as well as it should be. |
Update: 14 September 2026 Fuel prices reached a new high for the period since the Iran war began on 28 February 2026, the RAC said on 14 September 2026. Figures published by the motoring organisation on 11 September put average UK prices at 168.46p a litre for petrol and 190.08p for diesel, with petrol already at its highest level since September 2022. The previous diesel peak of the war period was 191.54p a litre on 15 April 2026. RAC senior policy officer Rod Dennis said on 11 September that oil had risen 6 dollars overnight to nearly 108 dollars a barrel, and that diesel was expected to hit a new war high within days. Both fuels rose about 7p a litre in the first eleven days of September, adding about 3.85 pounds to the cost of filling a typical family car, according to the RAC. Supermarkets were around 4p a litre cheaper than the UK average, and some independent forecourts were selling petrol below 158p. |
Update: 15 September 2026 The average UK pump price for unleaded petrol rose to 168.14p a litre in the week commencing Monday 14 September 2026, according to Department for Energy Security and Net Zero (DESNZ) weekly road fuel prices published on 15 September 2026. Diesel averaged 190.72p a litre. Both figures represent week-on-week increases, with petrol up 3.74p from 164.40p and diesel up 4.36p from 186.36p. Compared with the week commencing 31 August 2026, when petrol was 161.61p and diesel 183.49p, petrol has risen by 6.53p and diesel by 7.23p over a fortnight. Fuel duty remains unchanged at 52.95p a litre, and VAT is charged at 20 percent. The RAC media centre reported on 14 September 2026 that fuel prices had reached a new high for the Iran conflict period. The figures are based on DESNZ weekly road fuel prices. |
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Update: 22 September 2026 In the week to 21 September 2026, the UK average price of petrol stood at 172.0p per litre, while diesel averaged 195.5p per litre, according to the Department for Energy Security and Net Zero weekly road fuel prices published on 22 September 2026. The figures cover the seven days to 21 September and reflect pump prices across the UK. Fuel duty remains unchanged at 52.95p per litre until 31 December 2026. The rate has been held at that level, and the current duty position applies to both petrol and diesel for the remainder of the year. The weekly DESNZ data provides the official average pump price series used to track movements in the cost of road fuel. |
Update, 20 October 2026: petrol 174.57p, diesel 199.33p The Department for Energy Security and Net Zero's weekly road fuel price statistics, published on 20 October 2026, put the UK average pump price of unleaded petrol at 174.57p a litre in the week of 19 October 2026. That is down 0.71p on the week of 12 October 2026, when the average was 175.28p. The UK average price of diesel was 199.33p a litre in the week of 19 October 2026, also down 0.71p on the previous week's 200.04p. Diesel cost 24.76p a litre more than petrol on average that week. The figures come from the department's weekly road fuel price statistics. |
