UK petrol averaged 162.15p per litre in the week beginning 10 August 2026. Diesel averaged 181.97p, according to the latest DESNZ weekly road fuel prices. A 55-litre fill therefore cost about £89.18 for petrol or £100.08 for diesel.
Those prices replace the much lower March figures in the original version of this report. Petrol has risen 27.25p since 5 January. Diesel has risen 37.78p. This update explains the oil shock, the confirmed duty timetable, and the savings available from live local comparison.
What are UK fuel prices in August 2026?
The official 10 August averages were 162.15p for petrol and 181.97p for diesel (DESNZ, 2026). PetrolPal's live feed showed a similar 161.2p and 182.3p on 17 August across 8,064 stations (PetrolPal, 2026).
The weekly official series shows how quickly the market changed. Petrol moved from 149.80p on 6 July to 162.15p on 10 August. That is a 12.35p rise in five weeks. Diesel climbed by 17.20p, from 164.77p to 181.97p.
What does that mean at the pump? The five-week rise added about £6.79 to a 55-litre petrol fill. It added £9.46 to the same diesel fill. The last reported week alone added 2.26p to petrol and 2.78p to diesel.
The change since January is even sharper. On 5 January, DESNZ recorded petrol at 134.90p and diesel at 144.19p. By 10 August, petrol was 20.2% higher. Diesel was 26.2% higher. Drivers who planned around winter prices now face a different budget.
According to DESNZ, UK petrol averaged 162.15p per litre on 10 August 2026, while diesel averaged 181.97p. Those prices made a 55-litre fill cost about £89.18 and £100.08 respectively. The figures come from official weekly UK pump-price data.
For today's local prices, use PetrolPal's live UK fuel price map. National averages help with budgeting, but they don't show the cheapest station near your route.
Why did petrol and diesel prices rise?
Brent crude rose from $70.46 a barrel on 30 June to $93.26 on 11 August, a 32.4% increase (EIA, 2026). That sharp oil move raised the cost base for refiners and wholesalers before it reached UK forecourts.
Oil is priced in US dollars, so sterling also matters. A weaker pound makes each dollar of crude or refined fuel more expensive for UK buyers. Refinery costs, shipping, supply gaps, and demand then change the wholesale prices paid by retailers.
Why didn't every forecourt change by the same amount? Retailers buy on different schedules and hold different stocks. Some pass higher wholesale costs through quickly. Others delay a rise until cheaper inventory has sold. The reverse often happens when wholesale prices fall.
Diesel rose faster because drivers buy a finished road fuel, not crude oil itself. Diesel supply, refinery output, shipping space, and business demand can move separately from petrol. This helps explain the 20.63p diesel premium in PetrolPal's 17 August live averages.
The timing gap creates a practical signal. A national average can rise while one nearby station still sells older, cheaper stock. That window can be short, but live comparison can find it. Waiting for a broad price headline may mean missing the local difference.
EIA data shows Brent moved from $70.46 on 30 June to $93.26 on 11 August 2026. That 32.4% rise helps explain why UK pump prices increased through July and early August. Pump prices usually react after wholesale costs move because fuel must pass through refining, distribution, and forecourt stocks.
The RAC Fuel Watch page tracks daily pump and wholesale movements. It also records the 2022 peaks of 191.5p for petrol and 199.09p for diesel. August 2026 petrol remains below that record, but diesel is much closer.
How much of each litre is tax?
Fuel duty was 52.95p per litre on 10 August, and VAT was 20% (DESNZ, 2026). At 162.15p petrol, duty and VAT total about 79.98p, or 49.3% of the pump price.
VAT is charged on the full pump price, including fuel duty. At 181.97p diesel, the VAT part is about 30.33p. Add 52.95p duty and the tax total becomes 83.28p per litre, or 45.8% of the price.
Does a higher pump price always mean the government takes a larger percentage? No. Fuel duty is a fixed amount per litre, while VAT moves with the selling price. When wholesale costs rise, the duty share falls as a percentage, although the VAT amount increases.
This tax structure makes price rises feel uneven. A 10p pre-VAT cost increase becomes 12p at the pump after VAT. Drivers pay both the market rise and tax on that rise. The fixed duty does not cause the short-term move, but VAT adds to it.
At the 10 August official average, tax accounted for about 79.98p of each petrol litre and 83.28p of each diesel litre. Fuel duty was fixed at 52.95p, while VAT added about 27.03p to petrol and 30.33p to diesel. The remaining amount covered fuel, distribution, and retail costs.
The important point is now settled. The temporary duty cut does not end with one 5p jump. HMRC's confirmed timetable returns duty to its old rate in three stages.
What happens to fuel duty after August 2026?
Fuel duty remains 52.95p per litre through 31 August 2026. It then rises by 1p on 1 September, 2p on 1 December, and 2p on 1 March 2027 (HMRC, 2026).
If retailers pass each rise through fully, VAT increases the pump effect. September's 1p duty rise becomes about 1.2p per litre at the till. That adds roughly 66p to a 55-litre fill. The December step adds a further 2.4p per litre after VAT.
By 1 December, the two 2026 steps could add about 3.6p per litre against August's rate. That is roughly £1.98 on 55 litres. The March 2027 step brings the total pump effect to about 6p per litre, or £3.30 per 55 litres.
Could oil prices fall enough to hide the duty rise? Yes. Duty is only one part of the pump price. A drop in crude, refined product costs, or retailer margins could offset it. An oil rise could make the same duty change harder to see as a separate line.
HMRC confirmed that the 5p duty cut stays until 31 August 2026. Duty then rises in three steps, returning from 52.95p to 57.95p by 1 March 2027. With VAT, the full 5p duty restoration can add about 6p per litre if retailers pass it through.
Drivers should compare prices before and after each date, rather than assume every forecourt changes at midnight. PetrolPal's fuel price trends can show the wider movement, while the map shows nearby station prices.
Where can drivers still save money?
PetrolPal data on 17 August showed supermarket petrol averaging 158.83p, compared with 162.45p at branded forecourts (PetrolPal, 2026). The 3.62p gap is worth about £1.99 on a 55-litre fill.
For diesel, supermarkets averaged 178.64p and branded stations averaged 183.61p. That 4.97p difference is worth about £2.73 on 55 litres. These are group averages, not a promise that every supermarket beats every branded station.
What matters more, the badge or the number on the sign? Always the number. PetrolPal's data also showed independent petrol stations averaging 160.94p, between the supermarket and branded groups. A good independent can beat a nearby supermarket, especially when buying cycles differ.
Our live analysis covered 7,832 petrol prices and 7,924 diesel prices on 17 August. Petrol had a median of 160.9p, while diesel had a median of 181.9p. The close match between medians and averages suggests the national figures were not driven only by a few expensive stations.
PetrolPal measured a 3.62p petrol gap and a 4.97p diesel gap between supermarket and branded averages on 17 August 2026. On a 55-litre fill, those gaps equal about £1.99 and £2.73. A local price check can save part of the coming duty increase.
The government's Fuel Finder service requires changed prices to appear within 30 minutes. PetrolPal uses that official data to help drivers compare current forecourt prices. Check the detour cost before travelling farther for a small saving.
What should drivers expect for the rest of 2026?
DESNZ recorded a 12.35p petrol rise and 17.20p diesel rise between 6 July and 10 August 2026 (DESNZ, 2026). That speed shows why any exact year-end price forecast would be a guess.
Three signals matter most. First, watch Brent and refined fuel prices. Second, watch sterling against the dollar. Third, account for the confirmed duty rises on 1 September and 1 December. Retail margins and local competition decide how much variation remains between stations.
Could prices fall before December? They can. Oil moved sharply in both directions during 2026, and pump prices respond with a delay. A sound forecast uses ranges and clear conditions, not one target. The duty dates are certain, but the market around them isn't.
A useful household plan is to budget from the current 55-litre costs of about £89 for petrol and £100 for diesel. Treat any saving below that as a gain. If prices rise, compare locally before reducing essential journeys or changing where you fill.
DESNZ data shows petrol and diesel rose 8.2% and 10.4% respectively between 6 July and 10 August 2026. The duty timetable adds known pressure, but oil, currency, and local rivalry can soften it or add to it. Local prices remain the only number a driver can act on now.
Use the PetrolPal route planner to compare fuel stops along a journey. A cheaper station on your existing route usually beats a lower price that needs a long detour.
The latest official figures are 162.15p for petrol and 181.97p for diesel (DESNZ, 2026). These answers use the same 10 August release and PetrolPal's 17 August live data.
What should UK drivers do now?
Petrol at 162.15p and diesel at 181.97p make price comparison worth doing before a large fill (DESNZ, 2026). The 1 September duty step adds another reason to check nearby prices, but it doesn't remove local competition.
Keep three numbers in mind:
- £89.18 for a typical 55-litre petrol fill at the official average.
- £100.08 for the same diesel fill.
- 1.2p per litre as September's likely duty and VAT pump effect.
Don't chase a tiny saving through a long detour. Compare stations already near your route, check the update time, and use national trends for budgeting. The market can change quickly, but the cheapest practical forecourt is still a choice you control.
