Is it illegal to sell a Cat S or N car?

No — Cat S and N cars can be legally repaired and returned to the road. It IS illegal to sell one without disclosing the write-off. Always confirm the disclosure in writing.

Can I insure a Cat N car?

Yes, most mainstream insurers cover Cat N and Cat S vehicles. Premiums are usually similar, but the vehicle's market value is 20–40% lower.

What about Cat A and Cat B?

Cat A must be crushed whole. Cat B must be crushed as a bodyshell — usable parts can be salvaged. Neither category should ever return to the road; if one appears for sale, walk away.

Insurance write-off categories A, B, S and N explained

One in eight used cars on the road has been written off at some point. Most are safe, some aren't, and none should ever be a surprise. Here's how to tell them apart.

What is a write-off?

An insurer 'writes off' a car when the cost to repair it exceeds a percentage of its market value (roughly 60–70%). The car is then given a category based on the type of damage. The category stays on the vehicle record forever, even after repair.

The four categories

Category A — Scrap only

Severe structural damage. Must be crushed whole. No parts may be salvaged. If a Category A car turns up for sale it's stolen from a scrap yard — report it.

Category B — Body shell crushed

Extensive damage. The body shell must be crushed but serviceable parts (engine, gearbox, trim) may be recovered. The VIN is deleted. A Cat B car cannot legally return to the road; only its parts can be reused on other vehicles.

Category S — Structural damage, repairable

The 'S' stands for Structural. Damage to the chassis, subframe or crumple zones — the bits that keep you alive in a crash. Legal to repair and re-register. Only buy one if:

You have a full repair invoice from a reputable bodyshop.
The car has been re-registered with DVLA (it will have a V5C marked "structurally repaired").
An independent inspection has signed it off.

Category N — Non-structural damage

The 'N' stands for Non-structural. Cosmetic damage, electrical faults, water damage or interior damage — nothing that affects the safety cage. The most common category and the safest to buy, but still worth 20–30% less than an un-recorded equivalent.

Old-money: Cat C and Cat D

Before October 2017, Cat C (repairable structural) and Cat D (repairable non-structural) were the equivalents. You'll still see them on older cars. Treat Cat C like Cat S and Cat D like Cat N.

How to spot an undeclared write-off

Panel gaps that don't line up front-to-back.
Overspray on rubber trim, arch liners, headlamp housings.
Mismatched paint depth (a £30 depth gauge tells you fast).
New bolts on a car with old dirt everywhere else.
Airbag warning light that comes on and stays on.

The value hit

Rough rule of thumb for market value against an equivalent un-recorded car: Cat N loses 20–30%, Cat S loses 30–50%. Insurers will still cover them but many refuse if the repair provenance is thin.

Cat S, Cat N, Cat A, Cat B — write-offs explained