Build the mileage timeline first
Put the MOT readings and current advertised mileage in date order. Most cars should show a broadly rising sequence. Annual usage will vary, but a reading that moves backwards or jumps implausibly deserves a closer look.
Also compare the current mileage with the date of the most recent MOT. A seller may simply have typed the advert incorrectly, but it should still be corrected and explained.
Some discrepancies are genuine mistakes
MOT mileages can be entered incorrectly. Digits can be transposed, kilometres can be confused with miles, or an old instrument cluster can be replaced. One odd reading surrounded by a consistent long-term pattern may have an innocent explanation.
The key is evidence, not reassurance. Look for service invoices, workshop records, previous adverts or other dated documents showing mileage either side of the anomaly.
A mileage timeline that goes backwards
Illustrative example — the numbers below are invented to explain the checks.
| Test | Recorded mileage | Question |
|---|---|---|
| 2023 | 72,400 miles | Starting reference |
| 2024 | 81,100 miles | 8,700 miles added |
| 2025 | 18,600 miles | Why did the reading fall? |
| 2026 | 98,300 miles | What supports the corrected sequence? |
The isolated low figure could be an entry mistake, but that is a possibility to investigate, not a conclusion. Check the units on the original records, confirm that they belong to the same vehicle and compare dated invoices and any instrument-cluster replacement paperwork.
Build an evidence chain
Ask for documents immediately before and after the unusual reading, rather than one undated photograph. Note the date, registration, mileage and source of each document. A seller’s explanation is useful, but it is not independent verification of the mileage.
Decision: a coherent, documented explanation is different from an unexplained fall. When the evidence still does not add up, treat the mileage as unresolved and do not value the car as though the advertised figure were established.
Readings that only increase are not proof that the car’s mileage is genuine. CarSussed can flag a pattern in available records; it cannot certify every mile the vehicle has travelled.
Have a particular car in mind?
Check its available MOT records and mileage readings free. Then decide whether you need the full £9.99 buyer report.
What if the instrument cluster was replaced?
A legitimate cluster replacement can create a mileage mismatch if the displayed figure was not correctly carried over. Ask when and why it was replaced, who did the work and what the true vehicle mileage was at the time.
If the seller cannot explain which figure represents the actual mileage, future resale can also become difficult even if the mechanical condition is good.
When does clocking become a concern?
Concern rises when there is a material backwards jump, multiple inconsistent readings, wear that does not fit the displayed mileage, missing paperwork around the change, or a seller story that keeps shifting.
A discrepancy is not proof that somebody deliberately altered the mileage. It is a reason to keep the mileage status unresolved until the evidence makes sense.
Use the physical car as supporting evidence
Condition cannot prove mileage, but it can support or challenge the story. Look at steering wheel, pedals, driver’s seat, switchgear, door handles and general wear, while remembering that usage type and previous refurbishment can change how these areas look.
Service records and independent dated mileage readings carry more weight than appearance alone.
Should you buy a car with a mileage discrepancy?
Potentially, if the discrepancy has a clear and documented explanation and the car remains appropriately valued. If the true mileage cannot be established, treat that as a material unknown affecting price, confidence and future resale.
For an unexplained large discrepancy, another example is often the simpler purchase.
CarSussed approach: judge the pattern, the evidence and what still needs proving. A warning is not automatically a reason to reject a car, but an unexplained warning should change what you ask, inspect and pay.
Turn the evidence into a decision.
CarSussed checks the available vehicle evidence, explains the risks and gives you the questions and viewing actions to take before buying.
Sources and limits
GOV.UK: what is available in MOT history.
The worked examples are illustrative. CarSussed’s buying guidance is an interpretation, not an official MOT finding or a physical inspection.