Can you drive with a cracked windscreen?

A cracked windscreen is a common occurrence but, luckily, one that’s relatively easy to fix. Whether it’s caused by a loose stone that’s struck the glass at speed or by a weakness in the screen itself, it’s a job that needs carrying out as soon as possible.

Can you drive a car with a cracked windscreen?

You should avoid driving your vehicle if it has a cracked windscreen, as it could increase the chances of a car accident.

The Highway Code states that your vehicle must be roadworthy under Rule 97 (this is what an MOT determines, and why your vehicle needs one every year) and that your vehicle should be maintained according to the road vehicle regulations under Rule 89. It is these regulations that say all glass in the vehicle, including wing mirrors, windows and windscreens, should be looked after so as not to impair or obscure the driver’s vision.

Is it illegal to drive with a cracked windscreen?

The Highway Code, as mentioned above, states that all glass within your vehicle should be in good condition. However, the Highway Code is not itself a legal document, so can you be fined or charged for having a cracked windscreen?

Although the Highway Code cannot legally hold you to account, there is a separate Road Traffic Act that, under Section 40, states that a vehicle with a crack in the windscreen is classed as a vehicle in dangerous condition. You could receive up to three points on your licence and a fine if the crack is deemed to impair the driver’s vision.

However, this is where the rules can become a bit confusing. If your vehicle has a crack and goes for its annual MOT and passes, then the crack is legal and safe to drive with.

MOT test and cracked windscreen

The MOT test has certain regulations of its own when it comes to cracks. If the damage is bigger than 40mm in size anywhere on the windscreen, the car will fail its MOT and the crack would need to be repaired before you take it for a re-test.

However, you should imagine that your windscreen is cut into two zones - Zone A (in front of the driver) and Zone B (in front of the passenger). Any crack that falls within Zone A, even if it’s only 10mm in size, could result in an MOT failure.

This means that you may be able to drive a vehicle that has a small crack in the top left corner if it passed its MOT test, as this will not obstruct the driver’s view. But cracks can get worse over time and it shouldn’t be left for too long.

When to get your windscreen fixed

Try to get the crack fixed as soon as possible and only drive the car for emergencies until the repair has been completed. Not all insurers cover windscreens as standard, so check your policy. 

Driving with a damaged windscreen isn’t worth the risk, so don’t delay getting it repaired. Should the cracked windscreen be the cause of a car accident, you may be charged with driving without due care and attention.

Can a cracked windscreen be repaired?

A cracked windscreen should be replaced altogether. This is because even a small crack can quickly deteriorate into a large one, which could be dangerous. Windscreens generally help to strengthen your vehicle and this is why it’s so important that they’re kept in good condition. A windscreen with a crack, no matter how small, could weaken the overall structure of the vehicle.

How to stop a windscreen cracking further

You may have to drive your vehicle with a cracked windscreen if you’re unable to take it to a garage straight away. For instance, you may have booked it in to be repaired, but the appointment isn’t until the following week.

If you’re worried about the crack getting worse, is there anything you can do to prevent it?

The only thing you may be able to do is avoid large potholes in the road, as the impact could make the crack worse. However, this should only be done when safe to do so and you shouldn’t swerve severely in order to avoid one. Ensure that you have time to drive around it slowly and that there aren't any other vehicles or pedestrians around you.

Otherwise, there isn’t much you can do to prevent the crack from spreading further other than get the whole thing fixed.