An HPI check is a database search that reveals whether a car has outstanding finance, been written off by an insurer, reported stolen, or had its plates changed. For car flippers, it is one of the most important tools in your arsenal — it takes five minutes, costs £5–£20 depending on the provider, and can save you from buying a car that is legally compromised, impossible to insure normally, or impossible to resell at full price.
What a Full HPI Check Reveals
- Write-off status (Cat A, B, S, N): Whether an insurer ever declared the car a total loss. Cat A and B are permanently off-road. Cat S (structural damage) and Cat N (non-structural) can be repaired and sold legally — but with permanent value deductions
- Outstanding finance: Whether the seller still owes money to a finance company. The lender holds legal title until the loan is settled. Buying a car on outstanding finance means you do not legally own it
- Theft or stolen recovery: Cars that have been reported stolen and later recovered may have compromised documentation
- Mileage discrepancies: Cross-references official DVSA MOT records to detect odometer rollbacks ("clocking") — one of the most common forms of used car fraud
- Scrapped or permanently exported: Cars the DVLA has recorded as destroyed or shipped out of the UK — occasionally used in "ghost car" plate fraud
- Number plate changes: Multiple plate changes can be a sign the car's identity has been obscured
Why Outstanding Finance is the Biggest Risk
Unlike write-off markers (which reduce value but don't prevent sale), outstanding finance is a legal block on ownership transfer. Under UK law, the finance company retains a legal charge over the vehicle until the debt is repaid. If you buy a car with outstanding finance unknowingly, the finance company can legally repossess the car — from you, or from the buyer you sold it to. Your only recourse is to pursue the original seller for the purchase price, which is practically very difficult. Always check finance status before handing over a penny.
Understanding Cat S vs Cat N Write-offs
Category S means the car sustained structural damage — the chassis, A-pillars, B-pillars, sill sections, or crash structure were bent or compromised. Category N means the damage was non-structural — panels, bumpers, glass, airbags. Both categories permanently affect resale value and must be disclosed. As a trader, failing to disclose a write-off marker is fraud. Cat S cars carry a 20–35% value reduction; Cat N typically 10–20%.
If you knowingly buy a Cat S or N car, price your acquisition to reflect the reduced resale value, and always declare the status prominently in your listing. Buyers who know what they're looking at will still buy Cat N cars — they just expect the discount.
Going Further: vCheck and Salvage Database Searches
Standard HPI checks don't show you how bad the original damage was on a Cat S or N car. Platforms like vCheck and MotorCheck search UK salvage auction databases (Copart, Synetiq, e2e Total Loss Vehicle Management) and can show you actual photographs of the car when it was written off. This is invaluable for Cat S cars — you can see whether the repair looks clean or whether the chassis was heavily buckled. A £200 investment in a vCheck on a £6,000 purchase is excellent risk management.
The Rule Every Flipper Should Follow
Never, under any circumstances, hand over money without running a comprehensive background check. Run the HPI check before the viewing and verify the result on-site by checking the VIN plate matches the V5C and the windscreen VIN etching. The £10–£20 check cost is the cheapest insurance policy in the business.