Tyre faults at the MOT: the fail that barely changes with car age

The short answer

Most MOT faults get more common as a car ages. Tyres are the exception. Across models with 500 or more tests, the share of first tests failing with a tyre item sits between 3.2% and 4.9% for every first-used year from 2006 to 2021, in tests carried out 2021 to 2025. Roughly 1 in 25 cars, whatever its age.

That is because tyres wear with miles and time, not with the age of the car around them. Tread depth is the item recorded most, on 3.0% of first tests on cars aged 10 to 14 (44,980,002 tests). The legal minimum is 1.6 mm across the central three-quarters of the tread and all the way round, and as the wet, cold months start that depth is what holds the car to the road.

Tyre fails by the year a car was first used

All tests 2021 to 2025. The third column is the chance a first test failed with a tyre item. The fourth is a different measure, explained below.

Two ways to read the same number, and why one misleads

Look at the last column. Tyres featured in 54.7% of fails on cars first used in 2021 but only 10.4% on cars first used in 2006. Read carelessly, that says tyres are a far bigger problem on new cars. They are not. Young cars fail far less often, and when they do, worn tyres are one of the few things that can be wrong with them. The share of tests on those 2021 cars is 4.9%, much like everyone else.

The share of fails says what a fail was made of. The share of tests says how likely the fail was. For any comparison between groups, use the share of tests. The same trap runs the other way: a small tyre share of fails on a 2006 car does not mean its tyres are better, only that it has more other things to fail on.

The rules, and what to check

The Highway Code requires at least 1.6 mm of tread across the central three-quarters of the breadth and around the entire circumference. The DVSA inspection manual treats tread below the requirement as a dangerous defect. On the road, a defective tyre is endorsement code CU30 on the GOV.UK list: 3 penalty points, on the licence for 4 years.

1. Measure the tread with a gauge, several points round each tyre. The raised bars in the main grooves sit at the legal limit.
2. Check the inner shoulder on full lock. It wears first on many cars and hides from a glance.
3. Run a hand round each sidewall for cuts, bulges and cracking: the condition items the test records.
4. Set cold pressures to the door-pillar label.
5. Act on the pressure warning lamp. A tyre pressure monitoring system reporting a fault is itself recorded, on 0.7% of tests on cars aged 6 to 9.
6. Check the spare or sealant kit. Not a fail, but a long wait at the roadside.

Wheels and tyres are retested free if the car is back at the same centre before the end of the next working day. The GOV.UK MOT history service shows whether tyres were a minor item last year.

What this does not mean

A flat line across first-used years is not a flat line across cars. These are fleet figures pooled across every model; they say nothing about your tyres or any make. A high-mileage car wears tyres in a year; a little-used car cracks its sidewalls before the tread goes. The record also has no tyre brand or type, so nothing here says anything about winter tyres or any product. It shows what was found on the day, not why the tyre was still on the car.

Sources and method

Cohort shares are failed class 4 first tests, 2021-2025, involving at least one tyre item, across models with 500 or more tests, by first-used year (4,746,066 tests first used 2006 to 2,021,332 first used 2021), shown both as a share of all first tests and as a share of failed tests. Item shares are each tyre item as a share of all first tests in the age band (33,793,352 tests aged 3-5, 50,103,915 aged 6-9, 44,980,002 aged 10-14, 31,405,150 aged 15 and over).

• DVSA anonymised MOT results, class 4 first tests, 2021-2025 (data.gov.uk)
• GOV.UK: The Highway Code, annex 6, vehicle maintenance, safety and security
• GOV.UK: MOT inspection manual, section 5, axles, wheels, tyres and suspension
• GOV.UK: Endorsement codes and penalty points
• GOV.UK: MOT retests after a repair
• GOV.UK: Check the MOT history of a vehicle

This article is general information drawn from published test records. It is not professional, mechanical or legal advice, and an MOT pass or a clean MOT history does not guarantee that a car is roadworthy today. If you are unsure about a car, have it inspected by a qualified mechanic. You can check any vehicle's MOT history free on the official GOV.UK MOT history service.