
Headlights aren’t just there to help you see the road, they make sure other drivers and pedestrians can see you too. Whether it’s dark or the weather’s grim, working headlights are a must.
But what if one of your headlights suddenly goes out? Or worse, you’ve been driving around without realising only one is working? It happens more often than you’d think, but it’s something you need to fix straight away. Not only is it unsafe, but it could also get you pulled over and fined.
Here’s a breakdown of the law, the risks, and what to do if one of your headlights gives up.
Is it illegal to drive with one headlight in the UK?
Yep - it is. The Road Vehicles Lighting Regulations 1989 and the Highway Code make it clear: all your lights have to be working and clean. If you get caught with only one headlight:
- Police can issue a Fixed Penalty Notice (around £100, rising to £1,000 if it goes to court).
- You could get three penalty points on your licence.
- Your car will fail its MOT if all lights aren’t working.
So while some officers might let you off if it’s clearly just happened, it’s not worth the risk.
Why driving with one headlight is dangerous
It might not seem like a big deal, but one dead bulb can cause more issues than you think:
- Reduced visibility – You’ll struggle to see hazards properly, especially at night.
- Confuses other drivers – You could look like a motorbike in the distance.
- Higher accident risk – Uneven lighting makes you harder to spot and react to.
- Legal & financial pain – Fines, points, and higher liability if you’re in a crash.
- Possible electrical issues – Sometimes a blown bulb hints at a bigger problem.
What to do if a headlight goes out
If one of your headlights fails while you’re driving:
- Take it slow, keep your distance, and be extra cautious.
- Avoid driving at night if you can.
- Use high beams sparingly (don’t dazzle other drivers).
- Check that your brake lights and indicators are still working.
- Get the headlight fixed as soon as possible.
Quick DIY check: Park somewhere safe, switch on your headlights, and either look at your reflection (shop windows work well) or ask a mate to check both lights. If one looks dim or is out completely, it’s time for a fix.
How to replace a blown headlight
Changing a headlight bulb is usually pretty simple:
- Check your manual for the right bulb type.
- Switch off the engine and lights.
- Open the bonnet and find the headlight assembly.
- Remove covers/clips and disconnect the old bulb.
- Fit the new one (don’t touch the glass).
- Reattach everything and test it.
If you’re not confident or your car uses sealed units, just pop into your local garage and let the pros sort it. They’ll replace and adjust it for you quickly.
Driving with one headlight isn’t just illegal, it’s risky. Check your lights regularly and swap out dead bulbs ASAP to stay safe (and avoid fines).