What Are Cat S, Cat N and Cat B Cars? The Complete 2025 UK Guide to Insurance Write-Off Categories

What is a Cat S, Cat N, and Cat B car? The Complete 2025 UK Guide for Drivers and Sellers

Updated: October 2025 by the Second Gears editorial team

If you’ve ever typed “what is a Cat S, Cat N or Cat B car” into Google, you’re not alone. Thousands of UK drivers are searching for the same answer, especially those dealing with damaged, repaired, or written-off vehicles.

Whether your car’s been involved in an accident, flagged as a write-off by your insurer, or you’re simply browsing the market for a bargain, understanding what these categories mean can save you serious time and money.

This guide brings together insights from Carwow, Motorway, and Auto Trader, as well as the latest 2025 ABI Code of Practice, and explains how each category impacts value, insurance, and resale potential, particularly if you’re planning to sell your car through Second Gears.



The short version

Cat S (Structural): The car has suffered structural damage, for example to the chassis or crumple zones, but it can be safely repaired and put back on the road once inspected.

Cat N (Non-Structural): Damage isn’t structural but may involve key systems such as suspension, steering, or electrics. With proper repair and safety checks, these cars are often back on the road.

Cat B (Break for Parts): The car is too damaged to be driven again. It can only be dismantled for usable parts, and the remaining shell must be scrapped.

These categories replaced the older Cat C and Cat D system in 2017, shifting focus from the cost of repairs to the safety and structure of the vehicle.



Cat S — Structural but saveable

Cat S stands for Structural, meaning the vehicle’s frame or chassis has been damaged, but the car can still be made roadworthy after proper repairs. Insurers will usually write these off when the cost of repair outweighs the vehicle’s value, but many Cat S cars are successfully restored by skilled rebuilders and garages.

What sellers should know:
• Always disclose a Cat S status when selling. It’s a legal requirement and affects insurance and resale value.
• Keep a clear paper trail including photos before and after repair, geometry reports, and invoices. Buyers on marketplaces like Second Gears are more likely to trust a well-documented rebuild.

If you’re not looking to handle the repair yourself, Second Gears connects you directly with dealers and rebuilders who specialise in Cat S cars. You can get instant offers and sell without the headaches of auctions or time-wasting viewings.



Cat N — Non-structural, but don’t underestimate it

Cat N means Non-Structural, but that doesn’t always mean light damage. These cars might have suffered from steering or electrical faults, airbag deployments, or cosmetic issues that weren’t worth the insurer’s repair cost.

In reality:
• Most Cat N cars are repaired and safely returned to the road every year.
• Many owners drive them for years afterward without issues, provided the repairs are done properly.

If you’re selling a Cat N car, the key is transparency. Upload clear photos, repair details, and invoices to your listing. This reassures potential buyers and helps you achieve a better price on platforms like Second Gears, where our buyers are already familiar with these categories and value them realistically.



Cat B — Parts only

Cat B cars are the ones that can’t go back on the road. They’re often severely damaged, and while usable parts can be salvaged, the bodyshell must be crushed under strict ABI regulations.

However, that doesn’t mean they’re worthless. Engines, interiors, and electronics can often be worth more than you’d think. Second Gears provides a marketplace where you can sell Cat B vehicles for parts directly to authorised breakers and specialist buyers, saving you from being underpaid by scrap yards.



2025 regulations you should know

The ABI Code of Practice, updated in May 2025, sets out exactly how write-off categories are applied and how salvage must be handled. It also reinforces the strict no-road-return rule for Cat B vehicles and the specific structural checks needed for Cat S.

Platforms like Carwow, Motorway, and Auto Trader all align with these definitions, ensuring consistency across the UK market, and Second Gears uses the same standards to protect both sellers and buyers.



How categories affect value, insurance, and resale

Value: Cat-marked cars are usually cheaper than their clean-title equivalents, sometimes by 20 to 40 percent. However, demand for quality repaired cars is strong in 2025, especially for desirable models. The key is documentation. A Cat S or Cat N car with proof of professional repair can often sell faster and for more than people expect.

Insurance: Most insurers will still cover Cat S or Cat N vehicles, but you must disclose the category.
Checks that matter:
• Structural checks for Cat S including alignment and chassis integrity.
• Diagnostic and safety checks for Cat N covering airbags, ADAS, and electronics.
• Proof of parts and repair quality, especially if you plan to sell on Second Gears, since our buyers value transparency above all.



Common questions we hear at Second Gears

Can I drive a Cat S or Cat N car?
Yes, as long as it’s been repaired properly, passed a safety inspection, and is fully roadworthy. Cat A and Cat B cars can never legally return to the road.

Is a Cat N car just cosmetic damage?
Not always. Cat N cars can still have mechanical or electrical issues that require careful repair. The category simply means the structure wasn’t affected.

Why do some listings still mention Cat C or D?
Those are the older classifications from before 2017 that roughly correspond to Cat S and Cat N today. You’ll still see them on older vehicles and V5 documents.



How Second Gears helps Cat car owners

If your car has been marked as a Cat S, Cat N, or Cat B, you don’t need to struggle through time-consuming auction listings or lowball offers.

Second Gears is built specifically for people in your position, whether you want to:
• Sell a Cat S or Cat N quickly through our Instant Offers Tool, where verified dealers bid directly for your vehicle.
• List your car with repair photos and inspection proof to attract genuine buyers who understand its value.
• Sell a Cat B car for parts directly to licensed breakers, ensuring safe and legal disposal while getting the best possible return.

Our growing network of UK dealers, rebuilders, and traders means your car is seen by the right people from day one.



Search trends show what people really want to know

People across the UK are searching for:
• cat s vs cat n meaning
• is cat s worth buying
• can you insure a cat n car
• cat b breakers rules
• cat d vs cat n differences
• how much is a cat n worth compared to normal

This article answers all of those and shows how Second Gears helps you turn your damaged or written-off car into a fair, fast sale without the usual hassle.


Final thoughts

A Cat S or Cat N label doesn’t mean your car’s story is over, it just means it needs the right platform.

At Second Gears, we’re redefining how imperfect cars are sold. Our marketplace connects everyday sellers with trusted rebuilders and dealers who see value where others don’t.

So whether your car’s been recently written off, repaired, or just too much effort to fix, list it with Second Gears today and see what your vehicle is really worth.

Damaged doesn’t mean done. It just needs the right marketplace.