Cat A, B, S and N write-offs explained

What a write-off actually is

When an insurer pays out on a damaged vehicle it takes ownership of the wreck and records the loss on the Motor Insurance Anti-Fraud and Theft Register (MIAFTR). That record is permanent. It says the insurer judged the vehicle uneconomic to repair at that moment, given the repair estimate, the vehicle's value and the cost of a courtesy car. A cheap car with modest damage is written off far more readily than an expensive one with the same damage.

Because the decision is financial rather than technical, a written-off car may have been badly bent or barely marked. The category tells you which.

The four current categories

• Cat A — scrap only. The whole vehicle must be crushed, including every part. Nothing may be salvaged and it must never return to the road.
• Cat B — the body shell must be crushed, but serviceable parts may be removed and reused. A Cat B vehicle must never be re-registered or driven again.
• Cat S — structural damage. The chassis, crumple zones, suspension mounting points or other load-bearing structure were damaged. It can legally be repaired, re-registered and sold.
• Cat N — non-structural damage. Everything else: panels, lights, bumpers, electrics, trim, airbags, water ingress. Also legally repairable and saleable.

Cat S and Cat N replaced the old Cat C and Cat D in October 2017. The old letters described how much the repair cost relative to the car's value; the new ones describe what was actually damaged, which is far more useful to a buyer. Older cars still carry the historic C and D markers, and those records do not get retranslated.

Cat N is not automatically the safe one

Non-structural covers a wide range. A scuffed bumper is Cat N. So is a car whose airbags all fired, or one that sat in a flood up to the seat rails and now has corroding connectors and a wiring loom that will misbehave for years. Deployed airbags and water damage are both expensive and both non-structural. Never treat the letter as the whole story — ask for the loss date, the cause of loss and photographs or invoices from the repair.

What it does to the money

• Value. A properly repaired Cat S or Cat N car typically sells for meaningfully less than an equivalent car with clean history, and the discount follows it for the rest of its life.
• Insurance. Most insurers will cover a repaired Cat S or Cat N car, but some decline it, and a few load the premium. Confirm cover before you buy, not after.
• Finance. Many lenders will not fund a recorded write-off at all, which shrinks the pool of buyers when you come to sell.
• Warranty. Third-party warranties routinely exclude previously written-off vehicles.

Buying a repaired write-off sensibly

• Get the record first. Confirm the category, the date of loss and the recorded cause before you view.
• Ask who repaired it and demand the invoices. A VAT-registered bodyshop with a paper trail is a completely different proposition from a driveway rebuild.
• Have it inspected by someone independent, ideally with a paint depth gauge and a look underneath at the seams, sills and inner wings.
• Check the panel gaps, the boot floor, the spare wheel well and whether the tyres wear evenly on a test drive — pulling under braking or a crooked steering wheel suggests the geometry was never put right.
• Price it as a write-off. If the seller wants clean-history money, walk away.

The seller does not have to volunteer it

A private seller must not lie to you, but nothing obliges them to raise the subject. Traders selling to consumers are on a tighter leash and hiding a write-off is likely to be a misleading omission under consumer protection law — but neither rule helps you if you find out after the money has moved. Check the register yourself.

An EvelopCars report shows the write-off category, the date of loss and the recorded cause where our sources hold it, alongside salvage records, stolen markers and outstanding finance.