When an insurer decides a damaged car isn't worth repairing, or isn't safe to repair, it's declared a write-off and given a category that describes how badly it was damaged. If you're buying, selling or thinking of repairing an insurance-damaged car, the category tells you what you're dealing with.
Jump straight to what you're looking for:
Current UK insurance write-off categories
Since 1 October 2017, UK insurers have used four write-off categories, set out by the Association of British Insurers (ABI). Two mean the car can never return to the road (Cat A and Cat B), and two mean it can legally be repaired and driven again (Cat S and Cat N).
Cat S, structural damage (repairable)
A Category S (Cat S) car has suffered structural damage, damage to the chassis, frame or crumple zones that affects the core strength and safety of the vehicle. Examples include a bent or twisted chassis leg, a collapsed crumple zone or a damaged suspension mounting point.
- It can legally be repaired and put back on the road, but the structural damage must be professionally and safely repaired first.
- The DVLA must be notified, and the V5C logbook will permanently record the car as a Cat S write-off.
- Cat S cars are usually cheaper to buy than equivalent undamaged cars, but they're worth less when you come to sell, and some insurers charge more to cover them.
Cat N, non-structural damage (repairable)
A Category N (Cat N) car has suffered non-structural damage, the chassis and frame are intact, but repairing the car still cost more than the insurer was prepared to pay. Typical Cat N damage includes:
- Body panels, bumpers, doors and lights
- Electrical problems and infotainment or wiring faults
- Steering or suspension components (as long as the structure itself isn't compromised)
- Interior, flood or cosmetic damage
Cat N cars can legally be repaired and driven, and there's no legal requirement for a new MOT before returning to the road, but "non-structural" doesn't automatically mean minor. Steering, brakes and safety systems can be affected, so always have the repair inspected.
Cat A and Cat B, never to return to the road
Category A (scrap only): the car is so badly damaged that the entire vehicle must be crushed, not even individual parts can be salvaged.
Category B (break for parts): the bodyshell must be crushed, but undamaged parts (engine, gearbox, interior trim) can be stripped and reused in other vehicles. A Cat B car can never legally return to the road.
If you're offered a "bargain" car that turns out to be Cat A or Cat B, walk away, it cannot legally be registered for road use again.
Old write-off categories: Cat C and Cat D explained
Before October 2017, UK insurers used Cat C and Cat D instead of Cat S and Cat N. You'll still see these categories on older cars' histories, a car written off before the rules changed keeps its original marker, so it's worth knowing what they mean.
Cat C, replaced by Cat S
A Category C car was repairable, but the repair costs exceeded the vehicle's value, so the insurer wrote it off. The old system was based purely on repair cost versus value; the new system is based on the type of damage. Cat C broadly maps to today's Cat S, repairable structural damage. A Cat C car could be repaired and returned to the road, and many were.
Cat D, replaced by Cat N
A Category D car had lighter, non-structural damage, but the insurer still chose to write it off, often because repair costs plus admin (hire cars, delays, parts) made repair uneconomical. Cat D broadly maps to today's Cat N. Cat D cars were generally the least severely damaged write-offs, and used Cat D cars often represent the smallest price discount of the write-off categories.
Buying a Cat S or Cat N car: what to check
Written-off cars can be genuine bargains, typically 20 to 40% cheaper than an equivalent clean car, but only if you know exactly what you're buying:
- Run a vehicle history check before you view the car. It reveals the write-off category, when it was recorded, plus outstanding finance, mileage discrepancies and theft markers.
- Ask for repair evidence, invoices, photos of the damage and who carried out the work.
- Get an independent inspection, especially for Cat S cars, to confirm the structural repair was done properly.
- Factor in resale value, the write-off marker stays with the car for life, so it will always be worth less than a clean equivalent.
- Check insurance costs first, some insurers won't cover previously written-off cars, and others charge more. Compare quotes before you commit to the purchase.
What's my written-off car worth?
If your car has been written off, the insurer will offer you its pre-accident market value, what the car was worth immediately before the damage, not what you paid for it. You don't have to accept the first offer:
- Check what similar cars (same age, mileage, condition and spec) are selling for and use the evidence to negotiate.
- If you disagree with the valuation, you can challenge it and ultimately complain to the Financial Ombudsman Service.
- With Cat S and Cat N cars you can often buy the car back from the insurer (the settlement is reduced by its salvage value) and arrange repairs yourself.
Knowing your car's true market value, and its full history, puts you in a far stronger position, whether you're negotiating a settlement or deciding if a buy-back is worth it.
Selling a written-off car
You can legally sell a repaired Cat S or Cat N car, but you must tell the buyer it's a recorded write-off, hiding it is misrepresentation. To get the best price:
- Keep all repair invoices and photos to show the work was done properly.
- Consider an independent engineer's report, it reassures buyers and supports your asking price.
- Price realistically: expect a written-off car to sell below an equivalent clean car, with Cat N/Cat D cars holding value better than Cat S/Cat C.
- If the car is unrepaired, salvage buyers and specialist dealers will still purchase it, get several quotes.
Can I insure a car that's been written off?
Yes, repaired Cat S and Cat N (and older Cat C and Cat D) cars can be insured, but:
- Always declare the write-off history when you get quotes. Failing to declare it can invalidate your policy.
- Some insurers refuse previously written-off vehicles altogether; others may charge a higher premium or ask for an engineer's report.
- Shop around, specialist insurers are often more competitive for written-off cars than mainstream brands.
- If the car is later written off again, the payout reflects its reduced (write-off history) market value.
Getting a car insurance quote for a damaged or written-off car
The best way to find out what cover will cost is simply to compare quotes. When you do, have the write-off category (Cat S, Cat N, Cat C or Cat D), the repair details and any engineer's report to hand, declaring everything upfront means your policy is valid and your quotes are accurate. Comparing several insurers matters even more for previously damaged cars, because prices vary far more widely than for a clean car.
Write-off categories: quick answers
Is a Cat S or Cat N car safe to drive?
Yes, once properly repaired. Cat S cars need professional structural repair; Cat N cars need any safety-related components (steering, brakes, electrics) put right. If in doubt, get an independent inspection.
Does a write-off marker ever come off a car?
No. Once recorded, the category stays on the vehicle's history permanently and will show on any history check.
What's the difference between Cat C and Cat S?
Cat C (pre-2017) was defined by repair cost exceeding the car's value; Cat S (current) is defined by structural damage. They broadly cover the same kinds of cars, but the new system tells you more about the damage itself.
Do I need to tell the DVLA about a Cat S car?
Yes, the insurer or owner must notify the DVLA of a Cat S write-off, and the V5C is updated. For Cat N there's no DVLA notification requirement, but the marker still appears on history checks.