What is a Cat A, Cat B, Cat S or Cat N write-off?

There are four different categories for written-off cars. We explain them and consider the pros and cons of buying a write-off...

Crashed BMW 5 series Touring

When you’re browsing used cars for sale online, you might come across some that are significantly cheaper than the rest, and they could have a ‘Cat N’ label next to their listing. Cat N is one of four write-off categories introduced in 2017 by the Association of British Insurers (ABI), which regulates the salvage code for car insurers. While your immediate reaction might be to steer well clear of these cars, you could be doing yourself out of a bargain.

When cars are involved in accidents, a significant number of them get written off by insurance companies, because repairing them would cost more than they are worth. The reasons for this are twofold: more expensive and sensitive technology is being fitted to cars, and garage overheads are rising due to high fuel prices and inflation. As a result, a minor shunt that would once have cost a few hundred quid to fix is now likely to total more than £1000, once the repair work and the recalibration of systems are factored in.

Scrapyard car racks

Some of those written-off cars get sent to the scrap yard, but others are actually still fit to be on the road and can be resold once they’ve been repaired. The four categories reflect the level of damage sustained by written-off vehicles, with Cat N denoting that a car has suffered only minor damage that doesn’t affect its overall safety or driving integrity. 

It should be easy to identify a car that’s been written off as an uneconomic repair, because the Cat N label should be emblazoned across any advertisement from a reputable seller. If it’s not, a history check will provide you with this information.

The write-off categories in detail 

Category N: cars with non-structural damage  

This is one of two categories for cars that can be repaired and resold; the other is Cat S. The ‘N’ in the name stands for ‘non-structural’ and denotes that while these cars have been involved in an accident, they haven’t suffered damage to their structure. They might have sustained cosmetic damage to bumpers or other panels, or they might have mechanical or electrical problems that aren’t economically viable to repair.

Although the structural integrity of a Cat N car will still be intact, it might not be driveable, and some safety-critical parts, such as brakes, steering or suspension components, might need to be replaced. Although the Driver and Vehicle Licensing Agency (DVLA) must be informed that a car is a Cat N write-off, this information isn’t stated in the car’s logbook, so it’s important to get a history check to see if a car is listed as Cat N. 

Crashed Porsche 997 GT3 RS

Category S: cars with structural damage 

The ‘S’ stands for ‘structural’, which means cars in this category have sustained damage to their structural frame, but they can still be repaired and resold.

A Cat S car could have a bent or twisted chassis, or a crumple zone that has collapsed in a crash, so it must be professionally repaired and inspected before being allowed back on the road. Insurers are legally bound to destroy the original logbook of a Cat S car, and the repairer or buyer of it must apply for a replacement document that will have ‘Cat S’ stated on it. 

ebay scrapyard feature

Category B: cars that can be broken up for parts 

This designation stands for ‘break’ and means that although these cars have suffered extensive damage and are beyond repair, they contain some parts that can be removed and recycled. Once any salvageable parts have been removed, the bodyshell must be crushed.

Category A: cars that must be scrapped 

This category is reserved for the most badly damaged cars that must be crushed and never used on the road again. No parts from them can be reused, either. Even salvageable parts must be destroyed.

ebay scrapyard feature

How to approach buying a write-off

If you’re thinking of buying a write-off, follow these steps to stay safe and avoid ending up out of pocket:

1. Pay for a history check

If a seller is trying to make money by advertising a repaired write-off without disclosing the fact, this will show up in a history check. As well as confirming whether a car has previously been written off, some checks will provide you with details and photos of the damage the car sustained, helping you to judge whether or not you should buy it.

As with any used car, a history check will also tell you whether the vehicle has been stolen or is subject to any outstanding finance .

2. Get an inspection

Professional inspections

This will cost you upwards of £200, but it’s well worth the cost. An inspector knows what to check and could find accident damage that you haven’t spotted. The AA, RAC, Dekra and Autolign all offer inspection services that could save you from buying a potentially unsafe car.

3. Ask lots of questions

The insurer doesn’t have to release any information about how a car became a write-off, but some well-targeted questions to the seller can help you uncover what happened. The seller should be able to tell you what damage the car sustained, what parts were replaced and where the repairs were carried out.

4. Tell your insurance company

Make sure you inform your insurance company that the car is a Cat N. It will probably have to be noted on your policy, otherwise you risk having any claim turned down in the future.

5. Investigate a warranty

Some used warranty suppliers will provide cover for Cat N cars. It could be a surprisingly cost-effective way of giving yourself some peace of mind about your new purchase and any repairs that have been done to it.

What Car? says…

If you’re looking for a used car and see one that’s a Cat N write-off, don’t discount it immediately. If you can get a history check and detailed information about why it was written off, and you’re satisfied it has been professionally repaired, it’s worth considering. That said, it needs to be cheap enough to offset any hike in insurance costs you might incur, so you will need to weigh up all these factors before deciding if you want to go ahead and buy one.

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