UK Used Car Trade Terms Explained: A Glossary for Dealers and Buyers

A customer asking what a V5C is, or a new salesperson asking what a Category S write-off actually means, deserves a straight, accurate answer rather than trade jargon repeated back without explanation. This glossary covers the terms that come up most often around a used car sale, each one checked against an authoritative source rather than written from memory, because a glossary that gets its own definitions wrong is worse than no glossary at all.

V5C

The V5C is the vehicle's registration certificate, issued by the DVLA and commonly called the logbook. It records who DVLA has registered as the vehicle's keeper and the vehicle's registered details. It is not proof of legal ownership on its own, a distinction worth being clear about with a customer who assumes holding the V5C settles any ownership question.

HPI check

"HPI check" is used across the trade as a byword for a vehicle history check, but HPI is actually a specific provider's brand name (now part of Experian), not the generic legal term. A vehicle history check, whichever provider carries it out, typically looks for outstanding finance against the vehicle, a write-off or salvage marker, a stolen marker, and a mileage discrepancy against previous recorded readings.

VT20 and VT30

These are the DVSA's MOT test certificates. VT20 is the pass certificate, which has been optional to issue on paper since 1 September 2021 because results are recorded online. VT30 is the fail certificate, which generally still needs to be issued, though a further easement from 6 December 2023 means a paper copy can be skipped where the customer can access the result online and hasn't specifically asked for one.

SORN

A Statutory Off Road Notification tells DVLA that a vehicle is off the public road and therefore doesn't need to be taxed or insured for the time being. A dealer holding part-exchange stock off-road between intake and resale is the context this usually comes up in.

Trade plates

Trade plates (formally a trade licence) allow a dealer to move vehicles that aren't currently registered or taxed to the dealer, for purposes connected with the trade, such as test drives, delivery, or movement between sites, without taxing and insuring each vehicle individually in the meantime.

Part-exchange (PX)

A part-exchange is a customer's existing vehicle taken in as partial payment toward the car they're buying. Deciding what a part-exchange is actually worth and what to do with it once it's yours are two separate decisions, not one.

VED (Vehicle Excise Duty)

Commonly called road tax, VED is the tax paid to keep a vehicle on the public road. It's calculated differently depending on the vehicle's age, fuel type and original list price, which is why two superficially similar cars can carry a noticeably different VED cost.

Insurance write-off categories: A, B, S and N

The current four-category system (A, B, S, N) was introduced in October 2017, replacing the older A, B, C, D system. Category A means the vehicle must never return to the road and nothing from it can be reused. Category B means the shell must never return to the road, though individual parts may be salvaged. Category S means the vehicle had structural damage but can legally be repaired and driven again, and must be re-registered with DVLA before it is. Category N means the damage wasn't structural, but the vehicle still needs a careful inspection before resale since the underlying issue, electrical or mechanical, may not be obvious from a visual check.

Satisfactory quality

This is the core standard under the Consumer Rights Act 2015 that a used car sold by a trader has to meet: fit for purpose, free from minor faults a reasonable buyer wouldn't expect, and matching what the vehicle's age, mileage and price would lead a reasonable person to expect. It's a standard relative to the specific car's price and condition, not a single fixed bar every car must clear.

VAT margin scheme

A scheme letting a dealer account for VAT only on the profit margin on a qualifying used vehicle, rather than on the full sale price, provided the vehicle was bought without reclaimable VAT in the first place. The margin scheme has its own specific record-keeping requirements that are worth understanding properly rather than applying loosely.

GAP insurance

Guaranteed Asset Protection insurance covers the difference between what a motor insurer pays out if a car is written off or stolen and what the customer still owes on finance, or what it would cost to replace it. It's an optional add-on product, not a legal requirement, and like other add-ons sold alongside finance it sits within the FCA's fair value expectations for how it's priced and sold.

PDI (Pre-Delivery Inspection)

The PDI is the inspection carried out on a vehicle before it's handed over to a customer. A PDI that isn't documented is, in evidential terms, close to the same as a PDI that never happened, which is the main reason it matters beyond the inspection itself.

Clocking

Clocking means altering a vehicle's recorded mileage to make it appear lower than it actually is. It's illegal under UK consumer protection law regardless of who carries it out, and a dealer who unknowingly sells a clocked car still carries exposure under the Consumer Rights Act for having sold a vehicle that didn't match its description.

MYDEALERSHIPVIEW's vehicle record is built to hold a vehicle's documentation, history checks, and PDI findings together against that specific car, rather than scattered across separate systems or left to memory.

Bottom line

Most of these terms get used daily on a forecourt without ever being explained properly, to staff or to customers. Getting the definition right, and being able to explain it in plain terms when a customer asks, is a small thing that adds up to a dealership that comes across as genuinely knowledgeable rather than one reciting terms it hasn't actually thought through.

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