What an MOT history actually tells you (and what it does not)

The MOT history is the richest free record you have on a used car. Every test since around 2005 is there: the result, the mileage on the day, and the tester's own words for every defect and advisory. Read well, it is a maintenance diary. Read badly, it is a wall of jargon. Here is how to get the former.

What it does tell you

• The mileage at each test, which lets you see whether the car has covered a believable distance and whether any reading looks out of place.
• Recurring advisories, where the same fault appears test after test, which often means it was noted and never fixed.
• How the car has aged, since corrosion and wear are graded and you can watch them progress.

The pattern matters more than any single line. One advisory for a worn tyre is routine maintenance; the same corrosion advisory at three tests in a row, getting worse each time, is a repair that was noted and left, and a bill heading your way. Read the tests newest first, and pay attention to anything that keeps coming back rather than a one-off noted years ago and never seen again.

If you have not pulled the history yet, an MOT history check returns it in plain English alongside the rest of the free record.

What it does not tell you

An MOT is a snapshot of minimum roadworthiness on one day. A pass is not a clean bill of health, and it says nothing about service history, clutch wear, or whether the car has been in an accident that was repaired well enough to pass.

• It is not a service record. A car can pass every MOT and still have been poorly maintained between them.
• It does not cover write-off history, outstanding finance or a stolen marker, which are separate registers.
• A recent pass with no advisories on an older car is worth a second look, not blind reassurance.

For the checks the MOT cannot make, an insurance write-off in particular, it helps to understand the write-off categories. And used alongside a proper walk-round and test drive, the MOT history turns a stranger's car into something with a past you can read. Our used-car buying checklist puts it in order.