What is an insurance write-off?
Cat A and Cat B cars must be destroyed and can never be re-registered.
Spotted a category letter on a listing, an insurance renewal or a history check and want the whole picture before you dig deeper? This is the page to start on. It's part of our guide to car history checks.
A write-off isn't necessarily a wreck. An insurer declares a car a total loss when repairing it would cost more than the car is worth — or when it's too damaged to be safe. A minor knock on an older, low-value car can tip past that threshold even when the damage looks cosmetic, so "written off" is an accounting decision as much as a description of the wreckage.
The categories come from the ABI Code of Practice for the Categorisation of Motorised Vehicle Salvage — the industry rulebook UK insurers use to grade written-off vehicles, last updated on 28 May 2025. It's the primary source for every definition below.
The four write-off categories at a glance
| Category | Damage | Repairable? | Back on the road? |
|---|---|---|---|
| Cat A | Scrap only | No | Never — entire vehicle crushed |
| Cat B | Severe; body shell scrapped | No | Never — but some parts can be reused |
| Cat S | Structural | Yes | Yes, once properly repaired |
| Cat N | Non-structural | Yes | Yes, once repaired |
Cat A — scrap only
Cat A is the most severe grade. Per gov.uk, the car "cannot be repaired" and the entire vehicle has to be crushed — including the parts. Nothing can be salvaged, and DVLA will never re-register it. A genuine Cat A vehicle should never reappear for sale as a runner.
Cat B — parts only, body shell crushed
A Cat B car also "cannot be repaired" and can never return to the road as a complete vehicle, but there's one difference from Cat A: you can salvage other parts from it. The body shell has to be crushed, while serviceable components — engine, gearbox, lights, electronics — can be removed by a registered breaker and reused in other cars. So you might legitimately buy a Cat B part, but never a Cat B car to drive.
Cat S — structural damage, repairable
Cat S ("S" for Structural) means the damage reached a load-bearing part of the car — the chassis, frame or safety cell. It's repairable and can legally return to the road once it's been fixed properly, but structural repairs are harder to do well and harder to verify. Because of that, a Cat S car deserves a closer look than a Cat N one. For the full buying guide — paperwork, inspection, what to check — see our dedicated page on what a Cat S car is.
Cat N — non-structural damage, repairable
Cat N ("N" for Non-structural) means the car's structure and chassis were left intact — the damage was to panels, lights, electrics or trim. Don't read "non-structural" as "cosmetic", though: it describes where the damage is, not how serious it was. Brakes, steering, suspension or airbags can all be part of a Cat N write-off. It's repairable and road-legal once fixed. Our full guide on what a Cat N car is covers the buying checks in depth.
What happened to Cat C and Cat D?
If you're looking at older cars, you'll still see "Cat C" and "Cat D". Those are the old system. On 1 October 2017 the ABI replaced Cat C with Cat S and Cat D with Cat N, shifting the focus from repair cost alone to the type of damage — structural or not.
Crucially, the old markers didn't convert. A car categorised Cat C or Cat D before that date keeps its original marker for life; it does not become a Cat S or Cat N. So a pre-2017 Cat C or Cat D listing isn't a mistake — it's just the historic system.
Is a Cat S or Cat N car safe to buy?
It can be — with your eyes open. A well-repaired Cat S or Cat N car, priced to reflect its history, can be a genuine bargain. The marker stays on the car's record for life, so you're never paying for a clean title; you're paying for a car with a known past, at a discount.
The category itself doesn't tell you whether this car was repaired well — that comes down to the repair evidence, an independent inspection and the price. For the full breakdown on each, see our guides to Cat S cars and Cat N cars; Cat S in particular warrants an engineer's inspection of the structural repair before you commit.
How a write-off category affects you
Insurance
A previously written-off car must be declared to your insurer, and it can cost more to cover.
Finance
Financing a Cat S or Cat N car is often harder than financing a clean one. Some mainstream lenders decline or restrict lending on previously written-off vehicles; specialist lenders may still fund one, but often on tighter terms.
Resale value
The marker doesn't vanish with a good repair, so the next buyer sees it too — which means a smaller pool of buyers and less money than an equivalent car with a clean history. You'll see specific percentages quoted around the web, but they don't trace back to any published data source, so the safe assumption is simply "expect a meaningful discount, and expect to pass one on when you sell".
Selling a written-off car
If you're the one selling, don't hide the history. Whether you're a trader or a private seller, deliberately leaving out a material fact like a write-off can fall foul of UK consumer-protection law: since 6 April 2025 the relevant regime is the Digital Markets, Competition and Consumers Act 2024, which prohibits "misleading omissions". This is a general explanation, not legal advice; if you're unsure of your obligations, check gov.uk and Citizens Advice.
How to check a car's write-off category before you buy
Here's the catch that surprises a lot of buyers: the free government check doesn't show write-off category. Our own free car check shows the MOT record, mileage and current and historical tax status, but it won't tell you whether a car has ever been written off. That data sits on the insurance industry's total-loss register, not on DVLA's public record.
To see the category, you need a paid history check that draws on insurer-reported salvage data. Our Comprehensive check reports the write-off category (A, B, S or N) alongside outstanding finance, stolen markers, mileage anomalies and previous keepers. You can see a sample Comprehensive check report before you buy one.
One point on your rights: if you buy from a dealer, the Consumer Rights Act 2015 requires the car to be of "satisfactory quality" and as described, so an undisclosed write-off can give you grounds to complain. A private seller isn't held to that same statutory standard, though they can still be liable if they actively lie about the car. Either way, checking yourself first beats relying on recourse afterwards.
FAQs
What's the difference between Cat A, Cat B, Cat S and Cat N?
Cat A and Cat B cars must be destroyed and can never legally return to the road — the only difference is that Cat B parts can be reused. Cat S and Cat N can be repaired and driven again; Cat S involves structural (chassis or load-bearing) damage, Cat N doesn't.
Can a Cat A or Cat B car ever go back on the road?
No. Both are total losses that must be crushed, and DVLA will not re-register them. Only Cat S and Cat N cars can legally return to the road.
What happened to Cat C and Cat D?
On 1 October 2017 the ABI replaced Cat C with Cat S and Cat D with Cat N. Cars written off before that date keep their original marker — it doesn't convert.
Does a write-off category ever come off a car's record?
No. The marker is permanent. A good repair, a fresh MOT or the passage of time won't remove it, which is why it keeps appearing on history checks.
How do I check a car's write-off category before I buy it?
The free government check won't show it. Use a paid history check such as our Comprehensive check, which reports the write-off category along with finance, mileage and stolen-vehicle data.