Where mileage readings come from
No single body owns a complete mileage record. Readings get logged at MOT tests, at manufacturer service visits, and sometimes by previous owners on sale listings. Each is a separate snapshot taken at a different time by a different party, and they only get compared when someone pulls them together. A mileage check is really a consistency check: it's not confirming a single number, it's confirming the numbers climb the way a normal car's would.
What a genuine discrepancy looks like
- A drop between readings. Mileage should only go up. Any recorded drop is worth asking about directly.
- An unusually small jump for an older car. Very low annual mileage isn't impossible, but combined with heavy wear elsewhere, it's worth questioning.
- A large, sudden jump. Possible with genuine high-mileage use, but also consistent with a clocking attempt if it doesn't match the seller's story.
A single odd-looking gap doesn't confirm tampering on its own. Odometers can be replaced during a repair, a car can sit unused for a long stretch, or a reading can simply be entered wrong at a garage. Treat an inconsistency as a reason to ask questions, not proof by itself.
Running a check before you commit
The most useful version of this check pulls readings from multiple points across the car's life, not just the most recent MOT. A dedicated mileage check, like the one MOTCO runs against DVSA's MOT history, lines those readings up so a gap is easy to spot rather than something you have to work out from paperwork yourself. A ServiceBoss report does the same alongside manufacturer service dates.
Ask to see the car's V5C and any old MOT certificates alongside whatever check you run. Paper records and a digital check agreeing is a stronger signal than either alone.
Common questions
What counts as a normal annual mileage in the UK?
Roughly 7,000 to 8,000 miles a year for an average private car, though this varies a lot by usage. It's a rough benchmark, not a rule.
Can a mileage check be wrong?
Yes, if a garage entered a figure incorrectly at the time of a service or MOT. That's a data-entry error, not tampering, and it's usually a one-off gap rather than a pattern.