Will my tyres fail my MOT?

Tuesday 14th July 2026

A record 2.15 million vehicles failed their MOT due to tyre defects in the last year, making them one of the most common reasons for MOT failure. Our guide will explain each reason a tyre could fail, what counts as a minor advisory, and what you need to check before you book your test.

What tyre criteria do MOT testers check?

The MOT test checks the following tyre criteria:

• Tyre tread depth
• Condition of the tyre
• Tyre age
• Matching tyre type and fit
• Tyre pressure monitoring system, if your car is equipped with one

What is the legal tyre tread depth for an MOT?

The legal minimum tread depth for car tyres in the UK is 1.6 mm. MOT testers measure this across the central three-quarters of the tread, around the tyre's circumference, not just at one point.

The primary grooves of your tyres are the ones that count towards the tyre tread depth, not the secondary grooves and sipes.

Before your MOT

Perform a rough check on your tyres before your MOT with a 20p coin.

• Insert the coin into the primary grooves around the tyre
• If the outer rim of the coin stays visible, your tread is likely close to, or below the legal limit
• If in doubt, test with a  tread depth gauge

If tread is below the legal limit replace the illegal tyres before the date of your MOT test.

Can tyre damage fail my MOT?

Yes. Testers inspect the full visible surface of each tyre for cuts, lumps, bulges and tears.

A cut fails the test if:

• Any ply or cord is visible, regardless of the cut's size
• The tester opens the cut and finds cord underneath
• The cut is longer than 25mm or wider than 10% of the tyre's section width, whichever is greater, or a cord can be felt even if not seen

Lumps, bulges or tears caused by structural separation or partial failure are an MOT fail. This includes lifted tread rubber or exposed damaged cords.

These faults often follow a hard impact with a pothole or kerb. A damaged tyre can fail suddenly even while it's holding air, so MOT testers treat this as a dangerous fault.

Before your MOT

Visually inspect your tyres for any damage. If you see any significant damage, replace your tyres before your test.

Will cracked or perished tyres fail an MOT?

Rubber degrades over time, even on a tyre with plenty of tread left. Sunlight exposure and the ageing process harden the compound and cause it to crack, usually most visibly on the sidewalls of the tyre.

Testers assess cracking using the same criteria as other damage:

• Cracking that exposes the ply or cord will fail the test.4
• Cracks that appear where the tread meets the sidewall are considered most dangerous, as they can cause a blow-out.
• Surface cracking that doesn't reach the cord usually results in an advisory.

This matters most for low-mileage cars. While the tread might look as good as new, the rubber underneath may have turned brittle, particularly around the sidewalls where flexing is greatest.

Before your MOT

Check your tyre's date of manufacture, which can be found in the code on the sidewall. For standard cars, however, this isn't a formal part of the MOT test. As testers assess the condition they see on the day, there isn't an upper age limit for tyres.

Can incorrect or mismatched tyres fail an MOT?

Every tyre needs to be the right type for your vehicle, and all tyres need to be correctly matched.

Your tyres may fail if:

• You mix radial and cross-ply tyres on the same axle
• Tyres on the same axle, or on twin rear wheels, are different sizes
• A tyre's load or speed rating falls below your vehicle manufacturer's minimum requirement
• A tyre's load capacity is genuinely insufficient for the weight on that axle, in which case testers grade it as dangerous

Before your MOT

Check your vehicle's handbook, door jamb sticker or fuel flap for the correct specification and check your tyres meet that criteria.

Can tyre pressure fail an MOT?

Tyre pressure isn't tested as part of an MOT test but if any of your tyres are visibly under-inflated your vehicle will fail its MOT.

Before your MOT

Check your pressure against the figures in your handbook or fuel flap sticker.

Can a faulty tyre valve fail my MOT?

Testers grade a tyre valve if it's seriously damaged or misaligned to the point where it risks sudden deflation.

Before your MOT

It's a straightforward check but easy to overlook. Valve damage isn't always visible without removing the wheel or letting the tyre down.

Does the tyre pressure monitoring system (TPMS) affect my MOT?

TPMS inspection covers passenger cars first used on or after 1 January 2012. If the warning light indicates a genuine system malfunction, your car fails.

A TPMS light can also illuminate simply because it detected low pressure in the past. That's not the same as a fault. Where it's unclear which applies, testers record an advisory rather than a fail.

Before your MOT

If your TPMS light is on, it's worth getting it checked. A reset after a tyre change is sometimes all it needs.

What happens if my tyres fail the MOT?

The consequences depend on how the fault is graded. Here's how the main tyre defects break down:

• Dangerous defect: You cannot drive the car under any circumstances until it's repaired, not even to a garage.
• Major defect: The MOT has failed. Your car no longer has a valid certificate. You should only drive it directly to a pre-booked repair or retest.
• Minor defect: The car still passes. The fault is recorded on the certificate as something worth addressing, but it doesn't stop you driving away.

Driving on public roads with illegal tyres carries its own penalties, separate from the MOT result:

• Up to £2,500 fine per illegal tyre
• 3 penalty points per illegal tyre
• Four defective tyres risk a £10,000 fine and 12 points, enough to trigger driving disqualification

At Formula One Autocentres, we recommend replacing tyres once tread reaches 3 mm, well ahead of the legal limit. We stock a wide range of tyres to suit every vehicle and budget. You can browse our trusted tyre brands, compare prices, and even book your fitting online at your nearest centre.

Use our tyre search tool to find the perfect fit for your car and driving style and buy your tyres online today. Or if you're ready to book your MOT test, book online and save money by booking together with a service.