E10 comparison
E10 vs 91 unleaded
Compare E10 and regular unleaded 91, including vehicle compatibility, price differences, fuel economy, and when each option makes sense.
If you are planning a fill-up, continue with: Read: Premium vs regular fuel · Best time to buy petrol in Melbourne · Why diesel is more expensive than petrol · Melbourne fuel cycle explained · Read: How petrol prices work in Australia · Cheapest day to buy petrol (guide).
Reviewed by Petrol Price Near Me Editorial - May 2026
The basic difference
E10 is petrol blended with up to 10 percent ethanol. ULP 91 is regular unleaded petrol without that ethanol blend. E10 is often priced below ULP 91, but fuel economy can differ.
Before using E10, confirm your vehicle is compatible. Many modern petrol cars are, but some older vehicles, motorcycles, boats, and small engines may not be suitable.
Which is cheaper to run
E10 can be cheaper at the bowser, but the real saving depends on the price gap and your vehicle economy. If E10 uses slightly more fuel, it needs a big enough discount to remain cheaper per kilometre.
Compare the local E10 and ULP 91 prices on the day you fill, because the spread changes by station and suburb.
When to choose each fuel
Choose E10 when your vehicle is compatible and the discount is strong enough to offset any economy difference. Choose ULP 91 when compatibility is uncertain or the E10 discount is too small.
If your vehicle requires premium fuel, neither E10 nor ULP 91 may be appropriate.
Quick answers
Is E10 the same as 91?
No. E10 is an ethanol blend, while ULP 91 is regular unleaded. They can be alternatives only for vehicles compatible with E10.
Will E10 damage my car?
E10 should only be used in compatible vehicles. Check your manual, fuel flap, or manufacturer guidance if unsure.