Licence plate lights are straightforward to replace yourself in most cars

Your licence plate light is a small bulb mounted above or below your number plate that illuminates when your headlights are on. It fails more often than other exterior lights because it sits exposed to weather and road spray. Replacing it takes 5 to 15 minutes and costs between £3 and £15 for the bulb itself — far less than a garage visit. The job requires no special tools beyond what you probably have at home.

The process is straightforward: locate the light housing, remove the lens or cover, take out the old bulb, and install the new one. The hardest part is usually accessing the fixture, not the replacement itself. Most cars make this deliberately straightforward because it is a safety item — you need working licence plate lights to pass an MOT and to avoid being stopped by police.

Key Takeaways

  • Licence plate lights use small bulbs (usually 5W or 10W) that you can buy at any motor factors or supermarket for a few pounds.
  • Most housings twist out or clip free from behind the bumper, and the bulb either twists or pulls straight out once the housing is open.
  • Check your owner's manual or search your car's registration online to find the exact bulb type before you buy, because some cars use different sizes on each side.
  • If the light still does not work after you install a new bulb, the issue is likely a blown fuse or a wiring fault that needs a mechanic.

Locate your licence plate light housing

The light sits directly above or below your number plate, usually mounted in the bumper or the panel just above it. Look at the back of your car in daylight and trace the wiring or the small lens — it is often white or clear plastic. Some cars have one light in the centre, others have one on each side of the plate. Check your owner's manual if you cannot spot it; the manual will show you exactly where it is and how to access it.

Once you have found the housing, look at how it is attached. Most modern cars use one of three methods: a plastic clip that you press or squeeze to release, a twist-lock fitting that you rotate counterclockwise, or a small bolt or screw that you unscrew. Shine a torch behind the bumper if the light is mounted low — you may need to lie on your back or use a mirror to see the fastening clearly.

Remove the light housing from the bumper

If your light uses a clip, locate the clip on the back of the housing and press or squeeze it firmly. The housing should slide or pop out toward you. Do not force it — if it does not move, you may be pressing the wrong part. Some clips are on the side rather than the back.

If your light uses a twist-lock, grip the housing firmly and rotate it counterclockwise about a quarter turn. It should come free in your hand. If it is very tight, wrap a cloth around it for grip, but do not use pliers or a wrench — you can crack the plastic. For screw-mounted lights, use a screwdriver (usually Phillips head) to remove the bolt or screw and set it somewhere you will not lose it.

Once the housing is free, gently pull it away from the bumper. You will see the bulb holder inside — it may be a separate cartridge that twists out, or the bulb may be mounted directly in the housing. Do not touch the glass part of the bulb with your bare fingers if you are installing a halogen bulb, because skin oils can cause it to fail early. For standard incandescent bulbs, this is less critical, but it is still good practice.

Identify and remove the old bulb

Look at the bulb holder. If it is a cartridge (a plastic or metal tube with the bulb inside), twist it counterclockwise to release it from the housing. If the bulb is mounted directly in the housing, it will either twist out or pull straight out. Try twisting first — rotate it gently counterclockwise. If it does not move, it is a push-fit bulb; pull it straight toward you with a gentle, steady motion.

Once the bulb is out, look at the base. You will see a number or code printed on it — something like "5W", "10W", or "W5W". Write this down or take a photo. This is the wattage and type you need to buy as a replacement. Some cars use different bulbs on each side, so check both lights if you have two.

Buy the correct replacement bulb

Take the bulb code to any motor factors, Halfords, Tesco, or Asda — all stock common licence plate bulbs. Tell them the code and your car's year and model if you have it. They will hand you the right bulb. If you are ordering online, search for your car's registration on a parts website; it will show you the exact bulb type. Bulbs cost between £3 and £8 each, and you may want to buy two if both sides are the same type, so you have a spare.

Do not guess at the bulb type. Using the wrong wattage can blow the fuse, and using the wrong fitting will not go in at all. The code on the old bulb is your most reliable guide.

Install the new bulb and test it

Hold the new bulb by its base, not the glass. Insert it into the holder in the same orientation as the old one came out. If it twisted out, twist the new one in clockwise until it stops — do not force it. If it pulled out, push the new one in straight until you feel it seat fully. You should hear or feel a slight click if it is a push-fit bulb.

Reattach the housing to the bumper by reversing the removal process. If it was a clip, slide it back in until the clip locks. If it was a twist-lock, insert it and rotate clockwise until it stops. If it was a screw, replace the bolt and tighten it firmly but not so hard that you crack the plastic.

Turn on your headlights and check that the licence plate light comes on. Walk around to the back of the car and confirm the light is bright and even. If it does not light up, turn off the headlights, remove the housing again, and check that the bulb is fully seated. If it still does not work after you have reseated it, the fuse may be blown or there may be a wiring fault — this is a job for a mechanic.

What to do if the light still does not work

If you have installed a new bulb and it does not light up, the problem is not the bulb. The most common cause is a blown fuse. Your owner's manual shows you where the fuse box is and which fuse controls the licence plate light. Look for a fuse marked "number plate" or "tail light". If the fuse is blackened or the wire inside is broken, replace it with a new one of the same amperage (usually 5A or 10A). Fuses cost less than £1 and come in packs at any motor factors.

If the fuse is intact and the light still does not work, there is a wiring or connector fault. This is beyond a home repair — take the car to a mechanic. Do not ignore a broken licence plate light. It is an MOT failure, and police can stop you and issue a fixed penalty notice if it is not working.

Frequently Asked Questions

Can I use any bulb, or does it have to be the exact type?

It has to be the exact type. The wattage and fitting must match what your car was designed for. Using the wrong bulb can blow the fuse, damage the wiring, or not fit at all. The code on your old bulb (like W5W or 10W) tells you exactly what to buy.

What if I cannot get the housing out without breaking it?

Stop and check your owner's manual — you may be trying to remove it the wrong way. Some housings twist, some clip, and some screw. If the manual is not clear, a mechanic can remove it without damage in a few minutes. Forcing it risks cracking the plastic, which means buying a new housing (£20 to £50) instead of just a bulb.

Do I need to disconnect the battery before changing the bulb?

No. The licence plate light circuit is low-voltage and low-power. You do not need to disconnect anything. Just make sure your headlights are off before you start, so you do not accidentally touch a warm bulb.

How often do licence plate bulbs fail?

Incandescent bulbs typically last 500 to 1,000 hours of use. For a car driven daily, that is usually one to three years. LED licence plate bulbs last much longer (10,000+ hours) but cost more upfront (£8 to £15). If your bulb fails very frequently, the housing may be letting in water, and you may need a new housing.

Can I replace the bulb in the rain?

Yes, but dry the housing and your hands first. Water inside the housing can corrode the contacts and cause the light to fail again. If you notice water pooling inside the housing, the seal is broken and you need a new housing, not just a bulb.