Every UK Copart lot carries a category code assigned by the insurer who wrote the car off. The code is the single most important field on the listing. It dictates the legal status of the car, what you're allowed to do with it, what paperwork the DVLA expects, and (crucially for any flipper) how much the next buyer is going to take off the price.
The four current categories are Cat A, Cat B, Cat S, and Cat N. They were introduced in 2017 by the Association of British Insurers to replace the older Cat C and Cat D, which were widely misunderstood. The new system splits write-offs by structural versus non-structural damage rather than by repair-cost ratio: a cleaner signal for buyers.
The four categories at a glance
- Cat S
- Structurally damaged but economically repairable. Repair, inspect, re-register with DVLA. Resale haircut 25–40%.
- Cat N
- Non-structural damage. No DVLA re-registration required. Resale haircut 15–25%.
- Cat B
- Break for parts only. Body shell must be crushed. Not for flippers.
- Cat A
- Scrap only. No salvage permitted. You will essentially never see one at public auction.
Cat S in detail
A Cat S vehicle has had structural components compromised. That includes the chassis rails, A/B/C pillars, suspension turrets, subframes, sills, and crumple zones. The insurer judged that the cost to put right exceeded what they were willing to pay relative to the pre-loss market value — but the car can still be repaired competently.
What you legally must do: have the repair carried out (ideally documented), apply for re-registration through DVLA's V62/V23 process, and pass an MOT before the car is driven on public roads. DVLA permanently marks the V5 with the Cat S history. The marker doesn't go away.
Resale haircut: typically 25–40% off equivalent clean-title trade value. The discount is harshest in the year after repair and softens as the car ages, but it never disappears. A 10-year-old Cat S costs less than a 10-year-old clean-title example of the same model: that is the floor of the market.
When Cat S makes sense: when the structural damage is localised (a single wheel-corner hit, for example), the parts are cheap, and you have access to a frame jig or a body shop that does. When the buy-in is low enough that the resale haircut is already priced into your offer, Cat S can be one of the better margins on Copart UK.
When to walk: side-impact intrusion, B-pillar damage, multi-corner hits, or any roof damage. Repairing these properly requires straightening that doesn't fit a typical home-shop budget, and a sub-standard repair on a Cat S is the kind of thing that comes back later as a structural MOT failure or, worse, an insurance dispute.
Cat N in detail
Cat N covers everything that isn't structural — bumpers, panels, lights, glass, electrical faults, theft-recovery cosmetic damage, water-damaged interiors, engine bay fires that didn't reach the bulkhead. The insurer chose not to repair, but no chassis or safety-critical structure is involved.
No DVLA re-registration required. You repair, MOT, drive. The category marker still attaches to the V5 — that's automatic from the insurer's notification — but you don't need to apply for anything. This is the main practical difference from Cat S, and it's significant: re-registration is paperwork plus inspection plus weeks of waiting; Cat N skips all of that.
Resale haircut: typically 15–25% off clean-title trade value. Smaller than Cat S because the buyer pool is wider: anyone who reads the V5 carefully understands that "no structural damage" is meaningfully different from "structural repair, declared".
The catch: "non-structural" is the insurer's call, not a guarantee. Cars that should arguably have been categorised Cat S occasionally end up Cat N when the original assessor missed something. The vision pass on every CarMargin analysis cross-checks the visible damage class against the declared category and flags mismatches.
Cat B and Cat A
Cat B lots are for parts buyers. You can recover and resell components — engines, gearboxes, ECUs, body panels — but the body shell legally must be crushed. The DVLA expects a destruction certificate; without it, the V5 is invalid for re-registration on a different shell. Some buyers do treat Cat B as a back-door route to a body swap, but the paperwork side of that is fraught and outside the scope of this guide.
Cat A is destruction only. Even parts can't be recovered. Lots are usually scrapped before reaching auction; the few that do are clearly marked. There is no legitimate flip on Cat A.
How the category interacts with insurance
When you eventually insure a repaired Cat S or Cat N, expect:
- Some insurers refuse Cat S outright. Some refuse both. The mainstream comparison sites will quote them; smaller specialists are often more flexible.
- Premiums sit roughly 10–25% above clean-title equivalents. Less of an issue on cheap older cars, more painful on newer high-value ones.
- The insurer will want documentation of the repair — photos, parts receipts, ideally a body shop report. Keep everything.
- In a future total-loss event, the payout will reflect the category history. You won't get clean-title book value.
What CarMargin does with the category
Every Copart UK lot's category is one input to the deterministic max-bid solver. The solver applies a category-specific resale haircut to the AI-estimated retail value, on top of your target ROI, transport cost, fees, and repair plan. A Cat N gets a smaller haircut than a Cat S, and a Cat B is treated as a parts-out lot rather than a flip.
The vision pass also cross-checks: when a lot is declared Cat N but the photos show side-impact intrusion, CarMargin flags the mismatch. The category is what the insurer chose to write — not always what the damage actually is.
A buyer's quick rule of thumb
- Cat N — most accessible. Easiest paperwork, smaller haircut, widest buyer pool on resale. Good for first-time salvage buyers.
- Cat S — bigger margin per lot, more skill required. Frame jig access or a partnership with a body shop transforms the maths.
- Cat B — only if you're a parts breaker with somewhere to store and sell.
- Cat A — never.
Whichever category you bid on, read the listing's "Additional Information" notes carefully. The notes hide the most useful detail (no keys, missing title, mechanical fault) and routinely contradict the headline category. CarMargin parses them and prioritises red flags above the fold — but if you're bidding manually, it pays to read every word.