Is a Spare Car Key Worth It? The Maths Says Yes

Almost every all-keys-lost call-out we attend has the same postscript from the customer: "I always meant to get a spare." It is the single cheapest piece of motoring insurance available, and the numbers are not close.

The arithmetic

Cutting and coding a spare while you still hold a working key is a simple copy-and-learn job. Producing a key with nothing to copy means deriving the blade, reading the security PIN from the ECU and running an all-keys-lost programme, sometimes with a manufacturer-enforced security delay.

As a 2026 guide: a mainstream hatchback spare is around £120–£180, against £190–£280 for the same key when all keys are lost. A premium German smart key is around £200–£300 as a spare, against £320–£480 all-keys-lost. On top of the higher key price, an all-keys-lost event also costs you the disruption — a missed shift, a cancelled airport run, a day without the car.

The hidden costs a spare avoids

A car with no working key cannot be moved, which means it stays where it is, whether that is an airport short-stay car park accruing charges, a permit bay, or a supermarket with a two-hour limit and an ANPR camera. Add the taxi home, the taxi back, and any recovery if the location cannot be worked in safely.

Who should treat this as urgent

Anyone driving a car that came with only one key, especially a used purchase. Anyone whose only key is visibly worn, cracked, or has a hinge that flops. Anyone with a car over ten years old, where the original key has been in daily use the entire time. Van and small-fleet operators, where a single lost key idles a working vehicle for a day. And any household where one car is shared between several drivers.

Do it at your convenience, not in a crisis

A spare is a 20–40 minute mobile visit at a time and place that suits you — your driveway, your workplace car park. Store it somewhere other than the car itself, and out of sight of the front door if it is a keyless fob.

Call +44 7347 492822 with your registration for a fixed spare-key price across West London, Heathrow, Slough, Reading and the Thames Valley.