Understanding the UK's insurance write-off categories — and why neither means "unsafe" once properly repaired.
Since 2017, the Association of British Insurers (ABI) uses four write-off categories: A, B, S and N. Cars categorised A or B are destroyed for parts or scrap and can never be put back on the road. CAT S and CAT N are different — both can be legally repaired and returned to the road, and both are exactly what we specialise in.
| Category | CAT N — Non-Structural Damage | CAT S — Structural Damage |
|---|---|---|
| What it means | Damage does not affect the vehicle's structural integrity — typically cosmetic, electrical or minor mechanical damage. | Damage did affect a structural component (e.g. chassis rail, sill, suspension mount) which has since been professionally repaired. |
| Typical causes | Bumper damage, sensor faults, hail damage, theft recovery, interior damage, minor collisions. | More significant collision damage, larger impacts, or damage to load-bearing parts of the bodyshell. |
| Repair complexity | Generally simpler — panel, paint and electrical work. | Requires structural realignment on a measuring jig to manufacturer tolerances. |
| Safety once repaired | No different to any other properly repaired car. | No different to any other properly repaired car, provided the structural repair was done correctly by a qualified repairer. |
| Typical price discount | Moderate discount vs. an equivalent undamaged car. | Larger discount vs. an equivalent undamaged car, reflecting the more significant repair. |
Older write-off categories, Cat C (repairable, uneconomical to repair) and Cat D (repairable, but not necessarily due to damage), were retired in October 2017 in favour of CAT S and CAT N. The new system makes it explicit whether structural repair was involved — giving buyers clearer information than the old categories did.
If you ever see a car advertised as "Cat C" or "Cat D", it was categorised before the 2017 change — the equivalent modern categories are broadly CAT S (structural) and CAT N (non-structural).
Most mainstream insurers will cover CAT N & S vehicles, though premiums can occasionally be marginally higher, and some specialist finance lenders may ask additional questions. We always recommend disclosing the category to your insurer and shopping around — many of our customers insure these cars with no issues at all.
More Insurance & Finance FAQs →A seller who tells you exactly what was damaged and how it was repaired.
Structural work carried out by an insurance-approved bodyshop, not a budget backstreet job.
A post-repair inspection by someone other than the repairer themselves.
A current MOT and a written warranty giving you real recourse if anything goes wrong.
Every car sold by Second Chance Motors meets all four of these standards as a baseline, not an upsell.
