Cat S vs Cat N: Write-off Categories Explained

Cat S and Cat N are insurance write-off categories for cars that can legally be repaired and driven again. Cat S means the car suffered structural damage, to the chassis, body shell or crumple zones. Cat N means the damage was non-structural, which can still include brakes, steering, suspension or electrics. Both replaced the old Cat C and Cat D in October 2017, and DVLA records a Cat S category in the V5C logbook.

Write-off categories A, B, S and N

Insurers categorise written-off vehicles under a code of practice produced by the Association of British Insurers (ABI). There are four categories:

• Category A (scrap): can't be repaired. The whole vehicle must be crushed.
• Category B (break): can't be repaired. The body shell must be crushed, but some parts can be salvaged and reused.
• Category S (structurally damaged, repairable): can be repaired after structural damage and used again once roadworthy.
• Category N (non-structurally damaged, repairable): can be repaired after non-structural damage and used again once roadworthy.

Only S and N cars should ever appear for sale as complete, driveable vehicles. If anyone offers you a Cat A or Cat B car to drive, walk away.

Cat S car meaning

A Cat S car has damage to its structural frame or chassis. In practice that means things like a bent chassis leg, a damaged floor pan, a collapsed crumple zone or damage to the pillars and sills that hold the car's shape in a crash.

Structural damage matters because it affects how the car protects you in a future accident. The repair needs to put the structure back to its original dimensions, usually on a jig, with the correct welding methods and replacement parts. Done well, the car can be sound. Done badly, it can look perfect and still be unsafe.

The RAC's advice is blunt: a Cat S car isn't safe to drive until it has been professionally repaired.

Cat N meaning

A Cat N car was written off without structural damage. The insurer decided repairing it wasn't worth it, usually because the repair cost was high compared with the car's value.

Don't assume Cat N means "a few scratches". Non-structural damage can include:

• body panels, bumpers, lights and glass
• electrical faults and wiring
• brakes, steering or suspension components
• interior damage, for example after airbags deploy

A Cat N car on an older, cheaper model can be written off for damage that would be a routine repair on a newer car, simply because the car's value is low. That's why Cat N cars can be decent buys, and also why they vary so much.

Cat C and Cat D: what changed in 2017

Before 1 October 2017, repairable write-offs were Cat C and Cat D. Those categories were based mainly on the cost of repair compared with the car's value. Cat S and Cat N are based on the type of damage instead.

Two consequences:

• A car written off before October 2017 keeps its old C or D category. You'll still see these on older cars.
• There's no automatic conversion. A former Cat C isn't necessarily a Cat S, and a former Cat D isn't necessarily a Cat N.

What DVLA records, and what it doesn't

When a car is written off, the keeper must tell DVLA. You'll need your insurer's name and postcode, the reg and the 11-digit reference from the V5C, and you can be fined £1,000 if you don't.

If the owner keeps a written-off car, the insurer pays out and sells the car back to them. Then the rules split:

• Cat S: the keeper sends the complete logbook to the insurer and applies for a free duplicate V5C using form V62. DVLA records the vehicle's category in the logbook.
• Cat N: the keeper can keep the existing logbook.

So a Cat S car should show its category on the V5C, but a Cat N car's logbook may not. That's one reason why looking at the V5C alone isn't a full write-off check.

There is no longer a government inspection before a repaired write-off goes back on the road. The Vehicle Identity Check (VIC) scheme was abolished in October 2015. A repaired Cat S or Cat N car simply needs a valid MOT, tax and insurance. An MOT is not a structural repair inspection, so passing one doesn't prove the repair was done properly.

How to do a write-off check

The free DVLA vehicle enquiry service doesn't show write-off status, and neither does the MOT history. Use these steps:

1. Ask the seller directly and get the answer in writing.
2. Look at the V5C for a recorded category, and check the VIN on the car matches the logbook.
3. Read the MOT history on GOV.UK. A long gap followed by a test with lots of new parts, or a sudden change in mileage pattern, can hint at an accident.
4. Run a paid history check. Insurer write-off data is only available through paid checks.
5. Get an independent inspection by the AA, the RAC or a body repair specialist, who can look for signs of structural repair.

Practical tip: get an insurance quote using the reg before you pay a deposit. Insurers have access to write-off records, and a surprisingly high quote or a refusal can reveal a history the seller didn't mention.

A carVertical report can show a write-off category such as Cat S or Cat N where records exist, alongside damage records and photos from past listings, which can show the car before it was repaired. That's particularly useful for imported cars, whose damage history abroad won't appear in UK records. With the code KALOGB one report costs £31.99 instead of £39.99; see our carVertical discount code page. Our free car check guide covers what you can find out without paying.

Questions to ask the seller

Before you travel to see a repaired write-off, ask:

• What category is it, and when was it written off?
• What was damaged, and do you have photos from before the repair?
• Who carried out the repair, and can I see the invoices?
• Which parts were replaced, and were they new, used or pattern parts?
• For Cat S: was the body checked and straightened on a jig, and was the wheel alignment set afterwards?
• Have any airbags or seat belt pretensioners been replaced?
• How long have you owned it, and how many miles have you done in it?

A private seller who bought the car already repaired may not know all the answers, but a trader selling a repaired write-off should. Vague answers on a Cat S car are a reason to walk away.

Cat S vs Cat N: the practical differences

• Damage: S is structural; N is everything else.
• V5C: S is recorded in the logbook via a new V5C; N may not appear on it.
• Repair risk: S repairs need specialist structural work; N repairs vary from cosmetic to mechanical.
• Value and insurance: both usually sell for less than a clean equivalent, and some insurers won't cover written-off cars. The government's buyer guide says insurance can cost more and advises getting a quote before you buy.

Whichever category, you must tell your insurer the car is a repaired write-off. If you don't, your insurer can refuse to pay a claim.

Should you buy one?

It depends on the price, the quality of the repair and whether you plan to keep the car for a long time. We cover the pros, the cons and a full pre-purchase checklist in should you buy a Cat S or Cat N car?. Before buying any used car, also check its MOT history and the model's record in our reliability ranking.