The MOT Files

MOT defect file

Tyre worn close to the legal limit

Last updated

Quick answer

There is little usable tread left. Replace before it reaches the 1.6mm legal minimum across the central three-quarters of the tyre.

Typical cost
£70–£140 per tyre
DIY viability
Garage job

What you might notice

  • Tread blocks visibly shallow against the moulded wear indicator bars
  • Noticeably longer stopping distances in the wet, and standing-water aquaplaning
  • Wear concentrated on one edge, which points at alignment rather than age

What causes it

  • Normal wear — most tyres cover somewhere between 20,000 and 40,000 miles depending on compound, position and driving style
  • Under-inflation, which wears both shoulders while leaving the centre intact
  • Over-inflation, which does the reverse and wears the centre band
  • Misaligned tracking or worn suspension components, producing rapid wear on one edge only

Advisory or failure?

An advisory is recorded when tread is close to the limit but still legal. Below 1.6mm across the central three-quarters of the tread, around the entire circumference, it is a major defect and an automatic failure. Exposed cord or ply, a bulge, or a cut deep enough to reach the structure is a dangerous defect.

Can you fix it yourself?

Garage job

Fitting a tyre requires a machine, and the wheel must be rebalanced afterwards. Checking tread and pressures yourself is worthwhile and takes minutes — a 20p coin gives a usable rough guide, since the outer band of the coin is close to 1.6mm.

What it costs

Budget tyres for a common size start around £50 to £70 fitted; mid-range and premium sit between £80 and £160. Always replace in pairs across an axle, and if wear is uneven have the alignment checked at the same time or the new tyre will go the same way.

What happens if you ignore it

Driving on an illegal tyre carries a fine of up to £2,500 and three penalty points per tyre, so a car with four bald tyres can attract twelve points and a ban in a single stop. Wet braking performance falls off sharply in the last couple of millimetres of tread, well before the legal limit.

This is general guidance, not a diagnosis. The severity DVSA records depends on the specific fault found, so the same item can appear as an advisory on one test and a failure on another. Ask a qualified tester or mechanic to inspect the vehicle.

Has this been recorded on your car?

Check the full MOT history for any UK registration.

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