Insurance write-off categories explained: what are Cat N and Cat S cars?

New Cat S and Cat N insurance write-off classifications have replaced the old Cat C and Cat D groups; we explain all.

Car crash

​The UK’s insurance write-off categories were updated in October 2017, with Cat N and Cat S classifications replacing the former Cat C and Cat D. But what has changed aside from the names, and do the same caveats about buying a written-off car still apply?

The new categories were introduced to better reflect the increasing complexity involved in repairing modern cars, but it’s worth pointing out that cars originally classified as Cat C or Cat D won’t be reassessed, so there are some of these cars still for sale on the second-hand market.

When a car is involved in an insurance claim following an accident, or is damaged as a result of fire, flood or during a theft, its insurance company will assess it to judge if it’s worth repairing. In so doing, they will assign it a category, which determines how it should be viewed, and how it must be treated, in the future.

What is Cat S and Cat N damage?

A Cat S car is one which has sustained structural damage during a crash – think items such as chassis and suspension. While the car can safely be repaired and put back on the road, Cat S cars must be re-registered with the DVLA.

Cat N classification encompasses all non-structural damage, such as lights, infotainment and heated seats. As with Cat S cars, Cat N vehicles can be put back on the road, however, unlike Cat S cars, there is no need to re-register it with the DVLA – though you will still need to inform them your car has been written-off.

In effect, Cat N and Cat S replace the old Cat D and Cat C categories respectively, albeit with modifications to their remits.

What does Cat S and Cat N damage mean?

Updating the write-off categories means that buyers looking at vehicles which have been in a major accident will get a better idea of the type of damage sustained. What’s more, the registration certificate – the V5C – will now be marked with an ‘S’ to signify that the car has been salvaged, so buyers will be better alerted to cars with a write-off history.

The changes have not affected the Cat A and B classifications. Cat A cars have to be crushed, and none of their parts can ever legally be reused. Cat B (the ‘B’ stands for ‘break’) cars also have to have their body shells crushed, but can be broken up for parts before that happens, with salvageable components being resold.

Insurance write-off categories at a glance

  • A. Scrap
  • B. Break
  • S. Structurally damaged repairable
  • N. Non-structurally damaged repairable

Should I buy a Cat S or Cat N car?

The same caveats apply to Cat S or Cat N cars as apply to Cat C and Cat D vehicles: buyer beware.

One thing to be aware of is that insurance can be harder to come by for written-off cars, with some providers not covering them at all. While this can be overcome by hunting around, insurance for Cat S and N cars (likewise C and D) tends to be more expensive than it is for non-written-off cars.

Written-off cars are also worth less than their undamaged counterparts. While this should be reflected in their purchase price, you may find it hard to sell a Cat S or Cat N car, as some buyers will simply not consider them.

It’s also worth commissioning a thorough mechanical inspection from a qualified mechanic or engineer before buying a written-off car, and this particularly applies to Cat S cars, which have sustained structural damage.

Looking for a used bargain? Take a look at our Best cars for £5,000 or less...


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