Cat A, B, S or N Write-Off? What Each Category Means

See the letters Cat A, Cat B, Cat S or Cat N on a used car listing and it's worth stopping to work out exactly what you're looking at. These aren't marketing jargon or a vague warning. They're a formal classification system that tells you whether a car has been in a serious accident, whether it can legally go back on the road, and how much caution you should bring to the sale. Understanding insurance write-off categories properly can save you from buying a car that's either dangerous or simply worth a lot less than the asking price suggests.

The system has four tiers, and only two of them allow a car to be repaired and driven again. Here's what each one actually means, in order of severity.

The four insurance write-off categories explained

Category A: scrap only, no exceptions

A Cat A car is for scrap only, so badly damaged it should be crushed and never re-appear on the road, and even salvageable parts must be destroyed. This is the most severe classification going. No engine, no wheels, no infotainment unit, nothing gets a second life. If you ever see a car advertised as Cat A, walk away. It should never legally be on sale as a roadworthy vehicle.

Category B: broken up for parts

Cat B signifies extensive damage, although some parts are salvageable, and these vehicles should never re-appear on the road, although reclaimed parts can be used in other road-going cars. The bodyshell is destroyed, but mechanically sound components such as an engine or gearbox might get a second life in a different car entirely. A Cat B vehicle itself, however, is finished.

Category S: structural damage, but repairable

Cat S means the vehicle has suffered structural damage, which could include a bent or twisted chassis or a crumple zone that has collapsed in a crash, and the damage is more than just cosmetic, so the vehicle will need to be professionally repaired. Crucially, a Cat S car can return to the road once it's been properly fixed. But the process carries a formal step that Cat N doesn't: insurers must submit Form V23 to the DVLA as soon as the categorisation decision is made, without waiting for the V5C. It's then the keeper's responsibility to notify the DVLA when the vehicle is passed to the insurer following a total loss payment.

Category N: non-structural damage

Cat N covers damage that doesn't touch the load-bearing structure of the car. Think smashed lights, damaged wiring, a bent bumper mount or interior trim that's simply too expensive to fix relative to the car's value. No notifications are made to the DVLA or VOSA when a car is written off in a Category N situation, which is the key practical difference from Cat S. The car keeps the same V5C logbook, though a diligent seller should still be upfront about the history.

What happened to Cat C and Cat D

If you've been looking at cars for a while, you might remember Cat C and Cat D from older listings. Cat S replaced Cat C, and Cat N replaced Cat D in October 2017, with the new categories focusing more on the condition of the car rather than simply the cost of repairing it, according to the Association of British Insurers. The old system was purely about money: if repairs cost more than the car was worth, it got a category, regardless of whether the damage was a bent chassis rail or a scuffed bumper. The newer system asks what was actually damaged, which is far more useful information for a buyer.

Vehicles categorised as a Cat C or Cat D prior to 1 October 2017 keep that original marker, which is why you may still see cars advertised with these older labels today. If you spot one, treat it broadly the same as its modern equivalent: Cat C sits alongside Cat S, and Cat D sits alongside Cat N.

Can you actually buy and drive a Cat S or Cat N car

Yes, for Categories S and N. Once repaired, the car may need to be re-registered with the DVLA and must pass an MOT to confirm it's roadworthy. For a Cat S car that re-registration step via the V23 and V5C process is mandatory. For Cat N there's no formal DVLA re-registration requirement, but the car still needs to be genuinely roadworthy and pass its MOT.

It's possible to insure some written-off cars, but only if they've been properly repaired and are safe to drive. Some mainstream insurers are cautious about Cat S and Cat N vehicles, so it's worth getting a quote before you commit to buying, rather than after. Comparison sites are a sensible starting point for gauging what cover might cost and whether a particular insurer will even offer terms.

Money-wise, don't expect a like-for-like price with an equivalent car that's never been written off. Even after repair, written-off vehicles usually have a lower market value than equivalent cars with a clean history, so it's worth factoring this into your decision. A written-off marker follows the car for life; it doesn't disappear once the bodywork's been fixed and resprayed.

Who has to tell you

Professional car vendors and traders must state whether a car has been previously written off, though not all private sellers will tell you. That's the gap that catches out a lot of buyers. A trade dealer has a legal duty to disclose it. A private seller on a classified site might genuinely not know, or might simply leave it out.

How to check a car's write-off history before you buy

Never take a seller's word for it on write-off status, however honest they seem. A quick free check with our reg lookup tool gives you the car's MOT history, DVLA details, any outstanding safety recalls and a market valuation guide, all in one place and at no cost. That valuation is a rough indicator only, since real prices shift with condition, mileage, spec and demand, and it should never be treated as a guaranteed sale figure.

For write-off status specifically, along with outstanding finance, stolen markers, previous keepers, and any import or export history, you'll want our more detailed vehicle history check, which draws on Experian data to flag exactly this kind of background before money changes hands. It's a small outlay against the risk of buying a car that's structurally compromised or still owed money on finance from a previous keeper.

A written report from an independent inspector is worth having too, particularly for a Cat S car, since it gives you something concrete to point to if problems surface later, and a bit of leverage on price if they do.

What write-off status means for your money

Beyond the purchase price, a write-off history has knock-on costs. Premiums for Cat S and Cat N cars tend to run higher than for an equivalent clean-history vehicle, and resale value stays permanently reduced. If you're planning to fund the purchase rather than pay outright, it's worth checking early whether a repaired write-off is something a credit provider will fund at all, since some are more cautious about lending against them. You can look at general options via our car finance page; any finance offered is introduced only, subject to status and affordability, with no guarantee of acceptance.

If you're weighing up a Cat S or Cat N car against a clean one, our buying guides cover more of the practical checks worth running before you hand over a deposit.

The short version

Cat A and Cat B cars are finished as road vehicles, full stop. Cat S means structural damage that's been professionally repaired and formally re-registered with the DVLA. Cat N means non-structural damage that's been fixed but never needed DVLA sign-off. None of the four categories are inherently a scam, but each demands a different level of scrutiny, and none of them should be taken on trust from a listing alone. Run the checks, get an inspection if you're going near a Cat S car, and price in the fact that a written-off history never quite goes away.