Does a Cracked Windscreen Fail an MOT?

A cracked windscreen does not automatically mean your car will fail its MOT. The important factors are where the damage is, how large it is and whether it affects the driver’s view or the operation of the windscreen wipers.

Some chips and cracks may be recorded as advisories, while damage in a critical part of the windscreen can result in a failure. If a crack is spreading, obstructs your view or appears to affect the windscreen’s strength, it is sensible to have it assessed before driving more than necessary.

When can a cracked windscreen fail an MOT?

For MOT purposes, the windscreen is considered in different areas. The most important is the driver’s central view. This is the area directly in front of the driver, broadly centred on the steering wheel and within the part of the windscreen swept by the wipers.

As a general guide, damage larger than 10mm in the driver’s central view can lead to an MOT failure. In the rest of the windscreen’s swept area, damage larger than 40mm can also result in a failure. These measurements relate to the damaged area, not simply the length of one visible line, so a tester may need to assess the shape and extent of the defect carefully.

A crack outside the main swept area may not cause an automatic failure, particularly if it does not interfere with the driver’s view. However, larger damage can still be relevant. A tester will consider the overall condition of the windscreen, including whether the damage is likely to affect visibility or safety.

Why the position of the crack matters

A small crack close to the driver’s eye line can be more serious for MOT purposes than a larger mark near the edge of the windscreen. Damage in the driver’s view can catch sunlight, distort what you can see or become more distracting as it spreads.

The position also matters because the windscreen forms part of the vehicle’s structure. Modern windscreens can contribute to the correct operation of safety systems, including cameras or sensors mounted near the top of the glass. An MOT tester is primarily checking the items covered by the test, but damage around these areas should not be ignored.

The swept area is the part cleaned by the windscreen wipers. A crack in this section is more likely to affect visibility in rain, road spray or low winter light. Worn or damaged wipers may make the problem worse by leaving smears across the driver’s view.

Can a windscreen chip be an MOT advisory?

Yes. A chip or crack may be recorded as an advisory if it is not large enough, or not positioned in a way that meets the failure criteria. An advisory is not the same as a failure. It means the tester has identified a condition that may need attention later.

It is still worth taking an advisory seriously. Windscreen damage can spread after a change in temperature, a pothole impact or further vibration. A defect that is acceptable today may be larger by the next MOT, and a previously minor repair may no longer be possible.

If you are unsure what an advisory means or how soon to deal with it, our guide to what an MOT advisory means explains how advisories differ from failures and dangerous defects.

What if the crack is outside the driver’s view?

A crack outside the driver’s view is less likely to cause an MOT failure, but its position and size still matter. Damage near the edge of the glass can sometimes grow across the windscreen. It may also become more noticeable when the glass is under stress from temperature changes or rough roads.

Do not assume that a crack is harmless simply because it is on the passenger side. The windscreen still needs to provide a clear view through the areas used by the driver, and the tester must assess the condition of the glass as part of the MOT.

There may also be other reasons to arrange an inspection. For example, a crack can be accompanied by a loose piece of glass, sharp edges or damage caused by an impact that has affected surrounding parts. These details cannot be diagnosed accurately from a description alone.

Can you drive to an MOT with a cracked windscreen?

That depends on the condition of the windscreen and the legal status of the vehicle. If the crack seriously obstructs your view, is spreading rapidly or makes the glass appear unsafe, do not continue driving as normal. Arrange professional advice and consider recovery if necessary.

You must also have a valid MOT to drive on public roads, unless you are travelling to a pre-arranged MOT test or to a repair appointment after a failure, and the vehicle remains roadworthy. An MOT appointment does not make an unsafe car safe to drive. If the windscreen defect affects visibility, the vehicle may not be suitable for the journey even when an appointment has been booked.

Check the windscreen from inside and outside in good daylight. Look at whether the crack is directly in front of the steering wheel, whether it lies in the wiper-swept area and whether it is spreading. These are useful observations to share with a garage, but they do not replace a proper assessment.

What should you do before the MOT?

• Clean the windscreen so the full extent of the damage is visible.
• Check whether the crack is in the driver’s central view or within the swept area.
• Make sure the wipers clear the screen properly and are not split or damaged.
• Avoid pressing, picking at or attempting to enlarge the damaged area.
• Arrange a professional assessment if the crack is spreading or affecting visibility.

These are basic checks rather than a substitute for repair. Windscreen work can involve specialist materials, calibration and safety considerations, particularly on cars fitted with cameras or driver assistance systems. It is better not to attempt a repair yourself or remove any trim around the glass.

What happens if the car fails because of the windscreen?

The MOT result should explain the reason for the failure. Ask the tester to show you the area of concern and explain whether the issue relates to the size, position or effect of the damage. This gives you useful information when arranging the next step.

If the windscreen needs repair or replacement, the appropriate solution depends on the damage and the vehicle. A small repair may be possible in some circumstances, while a larger or poorly positioned crack may require replacement. The garage or windscreen specialist should explain what is suitable rather than promising that every chip can be repaired.

It is also useful to understand the rules around returning to the road after a failure. Our guide to driving your car after an MOT failure covers the main considerations. If your MOT is approaching, booking an MOT early can also give you more time to deal with defects without leaving the vehicle until the last minute.

How Ashton’s Garage can help

A windscreen defect is not always straightforward to judge by eye. At Ashton’s Garage, our approach is to inspect the vehicle properly, consider the location and extent of the damage, and explain what needs attention in plain language. We can also identify related issues that may affect the MOT, such as poor wiper performance or visibility problems.

If you would like the vehicle assessed as part of its MOT, you can find details of our MOT service in Salisbury. There is no need to guess whether a crack will pass. A sensible inspection can help you understand the position before the test and decide whether specialist windscreen work is needed.