Write-off categories: Cat A, B, S and N explained
What Cat A, B, S and N mean, what replaced Cat C and D in 2017, and what to ask before you buy a repaired Cat S or Cat N car.
Updated
A write-off category tells you how badly an insurer judged a car to be damaged. Cat A and Cat B cars must never go back on the road. Cat S (structural damage) and Cat N (non-structural damage) cars can be repaired and driven again. A repaired Cat S or Cat N car can be a fair buy at the right price, but only if you know the category before you pay, see proof of a proper repair, and have checked that you can insure it.
The short answer to "Cat S or Cat N" is that Cat S is the more serious of the two, because the damage was to the car's structure.
The four categories
| Category | What it means | Can it go back on the road? |
|---|---|---|
| Cat A | Cannot be repaired. The entire vehicle has to be crushed | No |
| Cat B | Cannot be repaired. The body shell has to be crushed, but other parts can be salvaged | No, though parts from it can be reused |
| Cat S | Can be repaired following structural damage, such as to the chassis or frame | Yes, once repaired to a roadworthy condition |
| Cat N | Can be repaired following non-structural damage, such as cosmetic or electrical damage | Yes, once repaired to a roadworthy condition |
These are the categories GOV.UK lists for insurance write-offs. The detail about crushing the Cat B body shell comes from the insurance industry's code of practice. A car is written off when the insurer decides it should not be repaired, or that repairing it would not make sense against its value. A Cat N car can have quite light damage on an older, cheaper car.
What happened to Cat C and Cat D
Cat C and Cat D were the old repairable categories. They were based mainly on the cost of the repair compared with the car's value. In October 2017 the insurance industry's code of practice replaced them with Cat S and Cat N, which are based on the type of damage instead.
You will still see cars advertised as Cat C or Cat D. They were written off before October 2017. The old category does not tell you whether the damage was structural, so treat these cars with the same care as a Cat S until the paperwork shows otherwise.
What the owner has to do
When a car is written off, GOV.UK says the owner must tell DVLA, and can be fined £1,000 if they do not. If the owner keeps a Cat S car, GOV.UK says the complete logbook goes to the insurer and the owner applies for a free duplicate with form V62. An owner who keeps a Cat N car can keep the logbook.
Cat A and Cat B cars should never reappear as complete cars. GOV.UK says that vehicles issued with a Certificate of Destruction must not come back on the road, and only minor parts can be taken from them. A car offered for sale as a whole car that was recorded as Cat A or Cat B is a reason to stop and walk away.
How to check the category
- Run a vehicle history check. Insurance write-off records are not on GOV.UK. A history check shows whether a car has been recorded as written off, and in which category. See how to check a car's history.
- Ask the seller in writing. "Has this car ever been written off or recorded in any insurance category?" Keep the answer.
- Read the advert closely. Phrases such as "light damage repaired", "recorded" or "cosmetic repair" can point to a write-off.
- Check the VIN. A repaired car should carry its own VIN, matching the V5C. A mismatch can point to a car rebuilt from parts. Our VIN guide shows where to look.
A history check only knows about write-offs that were claimed through insurance. A car repaired privately after a crash will not show as written off at all. That is why the viewing still matters.
What to ask about a repaired Cat S or Cat N car
The repair
Ask who repaired the car and ask for the invoice. A body shop invoice should list the parts and the work. Photos of the damage before repair are useful too. Be wary of a repair with no paperwork at all, or one the seller says they "did themselves" on a Cat S car.
The structure and safety systems
For a Cat S car, ask a mechanic or an independent inspector to look at the repair before you buy. Ask about wheel alignment, uneven tyre wear, panel gaps, paint that does not match, and any warning lights, especially the airbag light. If airbags went off in the accident, ask how they were replaced.
Insurance
Get an insurance quote with the category declared before you pay. Some insurers will not cover a Cat S car, and others charge more. You must tell your insurer about the category. If you do not, a claim could be refused.
Resale value
A written-off car is usually worth less than the same car with a clean history, and that stays true when you sell it. The asking price should reflect it. Check what similar cars with a clean history are selling for, and expect a clear discount.
MOT history
The MOT history can show problems that started after the repair. Our guide on how to read MOT history explains what to look for.
The duty to tell you
A dealer must not hide a write-off. Leaving out information a buyer needs to make a decision can be a misleading practice under consumer protection law. A private seller who lies when you ask directly is misrepresenting the car, and you may have a claim against them. Ask in writing so that the answer is on record.
If you discover after buying that a car was written off and nobody told you, keep the history check result, the advert and the messages, and get advice from Citizens Advice.
Frequently asked questions
What is the difference between Cat S and Cat N?
Cat S means the car had structural damage, such as to the chassis. Cat N means the damage was non-structural, such as to panels or electrics. Both can be repaired and driven again. Cat S is the more serious.
Is it worth buying a Cat N car?
It can be, if the price reflects the category, the repair is documented, and you can insure it at a price you accept. Get the insurance quote before you pay.
Can a Cat B car be repaired?
No. The body shell of a Cat B car has to be crushed. Parts from it can be reused, but the car itself must not go back on the road.
Does a Cat S car need a new MOT?
Being written off does not, by itself, change the MOT due date. The car must be roadworthy before it is driven, and the next MOT will test it like any other car.