Is super unleaded worth the extra over E10?

Most UK forecourts sell two grades of petrol: standard E10 and super unleaded, which is E5. We compared the price of both at every forecourt that reports them, by brand, nation and type of forecourt, and set the gap against what the government says about E10.

All prices are from the Fuel Finder snapshot at 06:47 on 17 September 2026. For today’s prices, use our UK fuel price finder.

How much more does super unleaded cost than E10?

Super unleaded (E5) averaged 189.0p a litre across the UK, 17.2p more than E10 at 171.8p. At forecourts selling both, the typical gap was 17.0p a litre.

Standard and premium prices across the UK

Both premium grades cost about 10% more than the standard fuel. Premium diesel carries the bigger gap in pence, at 19.5p a litre.

Fuel	Standard	Premium	Extra per litre	Extra on 55 litres
Petrol (E10 vs super unleaded E5)	171.8p	189.0p	+17.2p	+£9.46
Diesel (B7 vs premium diesel)	194.8p	214.3p	+19.5p	+£10.73

The UK averages cover slightly different sets of forecourts, because fewer sell the premium grades. That’s why we also compared prices at the same forecourt.

Comparing prices at the same forecourt

At the 5,954 forecourts reporting both petrol grades, super unleaded was a median 17.0p a litre dearer than E10. That comes to £9.35 on a 55-litre fill.

The mark-up varies a lot. 1,912 forecourts charged 20p or more extra for super unleaded, while only 762 charged 10p or less.

Twenty forecourts reported super unleaded cheaper than E10, which looks like keying errors. They barely move the median.

What does super unleaded add to the cost of a tank?

A 55-litre fill of super unleaded cost £103.95 at the UK average, against £94.49 for E10. That is £9.46 more every time you fill up.

What it adds up to over a year

The extra builds up quickly if you use super unleaded all the time. As an example, a driver filling a 55-litre tank every two weeks would pay £245.96 more over 26 fills.

That figure assumes prices stay at this week’s level, which they won’t. It shows the scale of the difference rather than a forecast.

Premium diesel costs even more

Premium diesel averaged 214.3p, 19.5p a litre above standard diesel at 194.8p. At the 4,016 forecourts reporting both, the median gap was 19.0p.

Fewer forecourts sell it: 4,143 report a premium diesel price, against 7,970 for standard diesel. On a 55-litre fill, premium diesel adds £10.73 at the UK averages.

Which brands charge the most for super unleaded?

Shell added the most, charging an average 22.5p a litre more for super unleaded than for E10 at the same forecourt. Maxol (9.3p), Tesco (10.3p) and Welcome Break (11.9p) added the least.

Super unleaded mark-up by brand

These figures compare the two petrol prices at each forecourt, then average them across the brand. We included every brand with at least 20 forecourts reporting both grades.

Brand	Forecourts with both prices	Average extra for super unleaded	Median extra
Maxol	50	9.3p	9.0p
Tesco	455	10.3p	10.0p
Welcome Break	38	11.9p	12.0p
Sainsbury’s	291	12.0p	12.0p
Murco	67	13.8p	15.0p
Texaco	356	15.8p	16.5p
Gulf	121	15.8p	18.0p
Asda Express	76	16.0p	16.0p
Jet	220	16.4p	16.0p
Esso	1,317	17.2p	18.0p
Morrisons	338	17.3p	17.0p
Valero	135	17.9p	20.0p
BP	954	18.3p	19.0p
EG On The Move	126	20.1p	20.0p
Shell	845	22.5p	23.0p

The big fuel brands against the supermarkets

Tesco and Sainsbury’s added 10.3p and 12.0p on average, with the motorway operator Welcome Break between them at 11.9p. Morrisons was the exception among supermarkets at 17.3p, level with Esso at 17.2p.

At Shell, super unleaded averaged 197.8p, and its 22.5p mark-up adds £12.38 to a 55-litre fill. BP added 18.3p, just above the UK median.

None of Asda’s 321 forecourts reported a super unleaded price in Fuel Finder. If you want E5 on an Asda run, check the prices near you first.

Where is the super unleaded premium smallest?

Northern Ireland had the smallest gap, with super unleaded 8.8p a litre above E10, about half England’s 17.5p. Supermarket forecourts also charged less extra, at 13.3p.

The premium by nation

On a 55-litre fill, the gap comes to £4.84 in Northern Ireland against £9.63 in England. Premium diesel shows the same pattern, at 6.7p above standard in Northern Ireland and 19.8p in England.

Nation	E10	Super unleaded	Petrol gap	Diesel (B7)	Premium diesel	Diesel gap
Northern Ireland	166.2p	175.0p	8.8p	189.7p	196.4p	6.7p
Scotland	172.9p	189.2p	16.3p	196.2p	215.3p	19.1p
Wales	171.1p	187.7p	16.6p	194.1p	212.5p	18.4p
England	172.2p	189.7p	17.5p	195.1p	214.9p	19.8p

Maxol, which has almost all its forecourts in Northern Ireland, had the lowest brand mark-up at 9.3p. The data can’t tell us why the premium is so much smaller there.

Related: Fuel prices in Northern Ireland

The premium by type of forecourt

Motorway services charged the most for super unleaded, at 208.4p a litre. Their 17.8p mark-up was a little below ordinary forecourts’ 18.3p, but it sits on top of a much higher E10 price.

Forecourt type	E10	Super unleaded	Petrol gap	Premium diesel gap
Supermarket	168.8p	182.1p	13.3p	13.8p
Other forecourts	172.5p	190.8p	18.3p	19.1p
Motorway services	190.6p	208.4p	17.8p	17.9p

We cover the motorway gap for standard fuel in how much more motorway services charge for fuel.

Does your car need super unleaded?

Probably not. GOV.UK says around 95% of petrol vehicles on the road can use E10, and all new cars made since 2011 are compatible.

Who should keep using E5

The government’s E10 petrol explained guidance says classic, cherished and older vehicles may not be compatible. The same goes for some models from the early 2000s and some mopeds, particularly those of 50cc or under.

You can check a car, motorbike or moped with the E10 vehicle checker. If your vehicle isn’t compatible, or you’re in doubt, GOV.UK says to keep using E5 super unleaded (97+ octane).

What if you put E10 in by mistake?

GOV.UK says a single tank of E10 in a vehicle that isn’t compatible shouldn’t be a major problem, and you shouldn’t need to drain the tank. Fill up with E5 next time, as GOV.UK says prolonged use of E10 in a vehicle that isn’t compatible may cause harm.

If your car is compatible with E10, GOV.UK says it’s safe to mix E5 and E10 in the same tank. In our data, 6,221 of the UK’s 8,072 forecourts report a super unleaded price.

Is super unleaded worth it for a car that can use E10?

On price alone, no. GOV.UK says E10 may reduce fuel economy by around 1%, while super unleaded costs about 10% more a litre.

Setting the 1% against the pump price

GOV.UK says the 1% drop is unlikely to be noticeable in everyday driving. It adds that driving style, under-inflated tyres or a roof rack have a much bigger effect on economy.

On a £94.49 E10 fill, 1% is about 94p. Super unleaded adds £9.46 to the same fill, roughly ten times as much.

We haven’t tested any performance claims made for premium fuels. This comparison is about cost only.

How we measured it

Every UK forecourt must report price changes to the government’s Fuel Finder scheme within 30 minutes. Our headline site averages and rankings use only E10 and standard diesel.

The super unleaded and premium diesel figures here are UK Motoring’s own calculation, using the same rules: we leave out prices unchanged for 14 days or that look like typing errors. The full rules are on our methodology page.

Premium diesel in the feed covers every brand’s premium diesel without naming the product. Our weekly fuel price email lists the cheapest petrol and diesel near your postcode.