Buying a used car in the UK comes with its own risks—especially if the vehicle has previously been written off. Two of the most common insurance write-off categories you’ll encounter are Category N (Non-Structural) and Category S (Structural). These classifications can significantly affect a car’s safety, value, and resale potential.
In this guide, we’ll show you how to identify a Cat N or Cat S car before buying and explain the implications of purchasing such vehicles.
Table of Contents
What are cat N and cat S cars?
- Cat N (Non-Structural): These vehicles have not suffered damage to the structural frame. The damage is cosmetic or affects non-critical parts like bumpers, lights, or interiors. Still, repairs may be costly, and the car may not be roadworthy until fully fixed.
- Cat S (Structural): These cars have sustained damage to the structure or chassis, such as crumple zones or suspension mounts. Even after repairs, structural integrity may be compromised if not fixed properly.
Both cars can legally return to the road, but it’s essential to understand what you’re buying.
How to spot a Cat N or Cat S car?
1. Ask the seller directly
Honest sellers should declare a car’s previous write-off status. If they hesitate or avoid the question, consider it a red flag.
2. Check the vehicle history report
The safest way to verify a Cat N or Cat S status is to run a Full Car Check via platforms which includes:
- Write-off status (including Cat S and Cat N, previously known as Cat C and Cat D)
- Date of incident
- Insurance company details
- MOT history & mileage records
- Outstanding finance
- Stolen status check
3. Inspect the V5C logbook
Check if the logbook (V5C) has been reissued recently. A new logbook after a write-off is a common indicator.
4. Physical Inspection
Look for:
- Mismatched paint or panels
- Misaligned doors or boot
- Uneven tyre wear
- Rust or recent welding in key areas
Consider taking a trusted mechanic or using a professional inspection service.
5. Cheap pricing
If a car is priced significantly below market value, it could be a Cat N or Cat S vehicle. Compare similar models to detect anomalies.
Should you buy a cat N or cat S Car?
Pros:
- Lower purchase price
- Good for short-term use or spare parts
- Potential resale value after full repair
Cons:
- Lower resale value
- Difficulty obtaining full insurance
- Safety concerns if not repaired to a high standard
- Limited warranty or finance options
Legal obligations in the UK
While it’s legal to sell a Cat N or Cat S car, sellers must declare the write-off status under the Consumer Protection from Unfair Trading Regulations 2008. Failure to disclose can result in legal action.
If you’re a buyer, insist on documentation, repair receipts, inspection reports, and detailed invoices. Buyers should also be aware that this status must be declared again when reselling the vehicle.
What checks can help?
When running a Full Vehicle History Check, look for:
- Write-off category (N/S) and date
- Previous MOT advisories
- Number of previous owners
- Salvage auction images (if available)
- Mileage discrepancies
A full car history check from The Auto Experts reveals Cat N or Cat S status, write-off details, MOT history, and more—all starting from just £5.99, making it one of the most cost-effective and reliable tools in the UK used car market.
It’s also recommended to run a stolen car check to ensure the vehicle has not been reported stolen alongside its write-off history.
Final Thoughts
Spotting a Cat N or Cat S car before buying can save you from costly repairs and insurance headaches. Don’t rely on seller claims alone. Use a trusted full car check service, inspect the vehicle thoroughly, and weigh up the long-term risks vs savings.
Frequently Asked Questions (FAQs)
1. Is it safe to buy a Cat N or Cat S car?
It depends on the quality of repairs. Cat N cars are generally safer as the damage is non-structural. For Cat S cars, insist on repair certification and independent inspection.
2. Can a Cat S or N car be insured?
Yes, but some insurers may offer limited cover or higher premiums. Always declare the write-off status during the insurance application.
3. Can you remove Cat N or Cat S status from a car?
No, once a car is written off and categorized, it retains that status permanently on its vehicle history.
4. Will a car check show Cat N or S details?
Yes. A full vehicle history check from providers like The Auto Experts will show write-off category, date, and other essential data.
5. Are Cat N cars better than Cat S?
Generally, yes. Cat N cars involve non-structural damage, which is usually easier and safer to repair. Cat S damage affects the car’s safety frame.
6. How much does a Cat N or Cat S car lose in value?
Cat N and Cat S cars typically lose 20% to 50% of their value, depending on damage and repair quality. Cat S cars usually lose more due to structural damage. A vehicle history check helps assess the impact before buying.
7. How can I check if a car is Cat N or Cat S?
You can check by running a vehicle history check using the registration number. It will show the write-off category, damage date, and other key details.