An insurance write-off is recorded when an insurer decides a vehicle is uneconomical or unsafe to repair following damage. The write-off record remains attached to the vehicle history — it does not disappear because the car has been repaired or sold. Understanding what each category means helps you decide how much weight to give it.
When a vehicle is damaged and an insurer assesses that the cost of repair exceeds a set threshold — typically a percentage of the vehicle's pre-accident value — it may be declared a write-off. The insurer pays the owner a settlement and assigns the vehicle a category based on the nature and extent of the damage.
The current UK write-off categories are A, B, S and N. Categories C and D were replaced by S and N in October 2017; older vehicles may still carry the legacy classification.
Category A is the most severe classification. A Cat A vehicle must be destroyed in its entirety. No part of the vehicle — including panels, mechanical components or the V5C document — may legally be salvaged or reused. A Cat A vehicle cannot return to the road.
A Cat B vehicle has damage severe enough that its body shell must be destroyed. However, some mechanical or electrical components may be salvaged and used elsewhere. Like Cat A, a Cat B vehicle cannot return to the road.
Category S (previously Cat C) means the vehicle sustained structural damage. The structural integrity of the vehicle was compromised — a bent or twisted chassis, damaged A-pillars, crushed sills, or other core structural elements.
A Cat S vehicle may legally return to the road after the damage has been professionally repaired and the vehicle has passed a DVLA inspection. It is not unsafe by definition — but the quality of the structural repair is critical. A poorly repaired Cat S vehicle may have ongoing weaknesses that affect safety and handling.
Category N (previously Cat D) covers damage that does not affect the vehicle's structural integrity — such as cosmetic damage, airbag deployment, electrical faults or water ingress.
A Cat N vehicle may return to the road without a formal DVLA inspection, as no structural work is required by definition. However, the quality of repair still matters. Cosmetic, electrical and airbag repairs can be done well or poorly, and a non-structural write-off can still represent a significant repair job that has not been carried out to a sufficient standard.
For any Cat S or Cat N vehicle, ask the seller for:
A recorded write-off — even Cat N — will typically reduce the vehicle's market value. Some insurers charge higher premiums or decline cover for vehicles with a write-off history. When you come to sell the car, the write-off will still be recorded and will factor into the next buyer's decision.
This does not automatically make a write-off vehicle a poor purchase. A car repaired to a high standard can represent fair value at a reduced price. The question is always whether the asking price reflects the recorded history, and whether the quality of repair can be independently verified.
A recorded write-off category is not a verdict on the car's current condition. What matters is the quality of repair and the documentation available to support it.
If a history check returns a write-off marker on a vehicle you are considering buying:
The Riskey History Check includes write-off category information where recorded. If the vehicle has a recorded write-off, the category will appear in the History Check result, helping you ask the right questions about the repair history and condition of the vehicle.
Enter the registration to check the vehicle's recorded history and get practical guidance on what to inspect, what may need attention next and whether the asking price makes sense.
Run a history check