Guide

Cat A and Cat B write-offs: the ones you can never buy back

Unlike Cat N and Cat S, a Cat A or Cat B write-off can never legally return to the road. Here's the difference.

jargon-busterUpdated 19 August 2026

Cat A and Cat B, defined

Cat A and Cat B are the two most severe insurance write-off categories in the UK, both meaning the vehicle must never go back on the road as a whole car. Cat A means the entire vehicle should be crushed; nothing from it, not even parts, is meant to be resold. Cat B means the body shell must be crushed, but usable parts can be salvaged and sold separately.

Why this matters for buyers

These categories exist for vehicles too dangerous to repair, typically after severe structural or fire damage. A car legitimately registered as Cat A or Cat B should never appear for sale as a complete, driveable vehicle again. If one does, that's a serious red flag, either an identity-cloning scam using a different car's paperwork, or a car illegally rebuilt from a crushed shell.

  • Cat A: whole vehicle scrapped, no parts resold
  • Cat B: body shell scrapped, individual parts can be resold

How to check before you buy

Because these vehicles shouldn't legally be on the road at all, a write-off check is the clearest way to protect yourself. For the more common Cat N and Cat S categories that DO return to the road legally, MOTCO's Cat N check confirms status against the registration before you commit to a price.

Trust the registration, not the paperwork in hand

Cloned identities exist specifically to get around checks like this by attaching a clean car's details to a written-off one. Always verify the VIN against the registration independently, not just the documents the seller shows you.

Common questions

Can a Cat A or Cat B car ever be re-registered?

No, not as a complete vehicle. These categories are specifically for cars deemed too dangerous to repair and put back on the road under any circumstances.

Are Cat A and Cat B still used as categories today?

The ABI updated its coding system in 2017 to add Cat S and Cat N, but Cat A and Cat B remain in use for the most severe cases, and older records still reference them.