Cat S and Cat N Cars: Should You Buy One? (UK Guide)

What the write-off categories mean

When a car is badly damaged or stolen and not recovered, the insurer may decide it’s uneconomical to repair and pay out instead. The car is then given a category:

• Cat A: scrap. The whole car must be crushed, with no parts reused.
• Cat B: break for parts. Some parts can be sold, but the body shell must be crushed. It can never go back on the road.
• Cat S: structural damage, for example to the chassis, subframe or crumple zones. It can be repaired and driven again.
• Cat N: non-structural damage, for example to panels, lights, trim or electrics. It can be repaired and driven again.

These categories replaced Cat C and Cat D in October 2017, so older cars may still show those. Roughly, Cat C was the old Cat S, and Cat D the old Cat N, though the old system was based on repair cost, not the type of damage.

“Written off” doesn’t always mean badly damaged

A write-off is a money decision, not a safety verdict. On an older or cheaper car, a minor accident can cost more to repair at insurer rates than the car is worth. A stolen car that was found later can also be written off. So a Cat N car might have had little more than a new bumper and headlamp, while a Cat S car might have had serious structural work. That is why the category alone doesn’t tell you enough.

Why they are cheaper, and the catches

• Lower price. Write-offs usually sell for noticeably less than the same car with a clean history. That’s the main attraction.
• Lower resale value. The marker stays on the car’s record for life, so you’ll get less when you sell it too. Some buyers and dealers won’t touch one.
• Insurance. Most insurers will cover them, but some refuse or charge more. Get a quote for that exact car before you buy.
• Finance. Some lenders won’t finance a write-off, or will lend less against it.
• Repair quality. The real risk. Repairs range from main-dealer standard to filler, second-hand parts and a quick respray.

How to find out if a car is a write-off

Insurers record write-offs on an industry register, and a paid vehicle history check shows them with their category. Run one before you pay, even if the seller says the car has a clean history, and check the result matches the car in front of you.

A dealer should tell you if a car is a write-off. A private seller may not mention it unless you ask, so ask directly and get the answer in writing, even as a text message. The free MOT history check won’t show a write-off, but a long gap between MOTs, or a big change in recorded mileage around one date, can be a clue that the car was off the road being repaired.

Checking a repaired Cat S or Cat N car

If you are happy with the price and the insurance, the next job is to judge the repair. Ask the seller:

• What happened, and what was damaged?
• Who repaired it, and can you see the invoice and photos of the damage?
• Were new or used parts fitted? Were the airbags replaced if they went off?
• Has it had a wheel alignment since the repair?

Then check the car itself:

• Panel gaps that are uneven, or panels that sit slightly proud of their neighbours.
• Paint that doesn’t quite match, overspray on rubber seals and trim, or paint that is much thicker on some panels than others.
• Under the bonnet and boot floor: crumpled or welded metal, fresh sealer, or brackets that don’t match.
• Warning lights on the dashboard, especially the airbag light, and stored fault codes.
• Tyres wearing unevenly, and on a test drive, the car pulling to one side or the steering wheel sitting off-centre.

For a Cat S car in particular, the structure matters most, and it is hard to judge on a driveway if you don’t know what you are looking at. This is where an independent inspection earns its cost. Our inspectors check every panel for signs of repair, scan the car’s computer for stored fault codes, and road test it. Ultimate adds paint thickness readings. See what each package includes, from £69.99.

When to walk away

• The seller denies it’s a write-off and the history check says otherwise.
• There is no paperwork for a Cat S repair and the seller can’t say who did it.
• The airbag light is on, or airbags were not replaced after they went off.
• The price is close to a clean car’s price. The discount is the only reason to take on the risk.
• You can’t get insurance at a sensible price.

So, should you buy one?

A well-repaired Cat N car bought at the right price can be good value, especially if you plan to keep it for years. A Cat S car can be too, but the bar is higher: you want proof of a proper structural repair and an independent check before you pay. If anything about the repair or the paperwork doesn’t add up, there are plenty of clean cars for sale.

Get the repair checked before you buy

We inspect cars at the seller’s address, the dealer or your home, and you get a written report with photos, often the same day. See a sample report or book an inspection.