Unleaded vs super unleaded: which does your car need?
Published on 2026-06-08
Super unleaded costs more per litre than standard E10. Is it better for the engine, or are you overpaying? It depends on what your car asks for, not the marketing.
What the octane number means
Standard unleaded in the UK is E10 (95 octane); super unleaded is 97-99 octane. Higher octane resists pre-ignition under higher compression — which some performance and turbo engines need. It isn't simply 'more powerful'.
What does your car need?
Check the manual or the filler flap. If it says 95/E10, standard is fine. If it specifies 'super unleaded' or a minimum octane, use it. Putting super in a car designed for 95 won't harm it, but you usually pay more for no real gain.
What about E10 vs E5?
E10 (up to 10% ethanol) is the standard grade; E5 is now mostly the super-unleaded grade. Almost all petrol cars built since 2011 run fine on E10 — check the government's E10 compatibility checker if your car is older.
FAQ
Can I put super unleaded in a normal car?
Yes, it won't harm it. But unless the maker asks for it, you won't notice a benefit and you'll pay more.
Is E10 safe for my car?
Almost all petrol cars made since 2011 are E10-compatible. Older or classic cars should check the official E10 checker and may need E5.
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