The four current categories
UK insurers categorise written-off vehicles into four bands under the Association of British Insurers (ABI) Code of Practice for the Categorisation of Motorised Vehicle Salvage. The current version, V12, took effect in May 2025.
Cat A is the most severe — the entire vehicle must be crushed and no parts may be salvaged. Cat B vehicles are also destroyed at body-shell level, but mechanical and electrical parts may be reused. Cat S covers structural damage that has been or can be properly repaired. Cat N covers non-structural damage — cosmetic and mechanical issues that don’t involve the load-bearing frame.
Cat C and Cat D — the retired markers
Before October 2017, the UK used Cat C and Cat D instead of Cat S and Cat N. The old system was cost-based: it asked whether repair cost more than a percentage of the vehicle’s pre-accident value. The current system is damage-based: it asks what was actually damaged.
Vehicles categorised before October 2017 keep their Cat C or Cat D marker forever. The markers don’t convert to the new system, and they remain on the V5C and on history check databases.
Why the category matters when buying or insuring
The category determines whether the vehicle can return to UK roads (Cat S and Cat N can; Cat A and Cat B cannot), what insurers will quote on it, and what discount applies on resale. A Cat S marker typically attracts a 30–50% discount on book value; Cat N is usually 20–40%.
The marker is permanent. It can’t be removed by repair, by passing an MOT, or by time elapsing. Any history check via HPI Check or Experian AutoCheck will return it.