Number plate lights are straightforward to replace yourself in most cars

The light that illuminates your number plate is one of the easiest bulbs to change on your vehicle. In most cars, you can do it in under five minutes with no tools beyond a replacement bulb. The bulb sits in a small fixture mounted directly above or below the plate, and you access it from behind the bumper or from inside the boot. Once you know where it is and what size bulb your car uses, the swap takes longer to describe than to do.

A dead number plate light is also a traffic violation in most places — police can stop you for it, and you may face a fine. Replacing it promptly keeps you legal and takes almost no time or money.

Key Takeaways

  • Number plate lights are accessed from behind the bumper or from the boot, depending on your car's design.
  • You need to know your bulb size before you buy a replacement — check your owner's manual or the existing bulb itself.
  • Most replacements require no tools; you straightforward twist or pull the bulb holder out and swap the bulb.
  • If the light still does not work after you replace the bulb, the wiring or fixture may be faulty and you should see a mechanic.

Locate the number plate light fixture on your car

Number plate lights are mounted in the bumper area, either directly above the plate or on either side of it. On some cars, the fixture is accessible from outside the bumper; on others, you reach it from inside the boot. Open your boot and look at the inside surface of the bumper panel — you will often see the back of the light fixture protruding through, with a small plastic or rubber cover you can twist or pry off.

If you cannot see it from the boot, the fixture is likely mounted on the outside of the bumper. Get down and look directly above and below your number plate. You will see a small rectangular or circular plastic cover, usually black or grey. This is the lens. The bulb holder sits behind it.

Your owner's manual will show you the exact location for your model. If you do not have the manual, search online for "[your car make and model] number plate light location" — forums and YouTube videos from other owners of the same car are usually accurate.

Find out what size bulb your car needs

Bulb sizes are labelled with codes like W5W, T10, 501, or 194. The easiest way to find yours is to look at the existing bulb. If it is still intact, the code is printed on the base. If it is blown, check your owner's manual — the bulb specification is usually listed in a section called "Bulbs and Fuses" or "Maintenance".

You can also call your car's dealership with your registration number and ask them the bulb size. They will tell you in seconds. Once you have the code, buy a replacement at any motor factors, supermarket, or online retailer. A single bulb costs between £1 and £3.

Buy a standard incandescent bulb unless your car originally had an LED unit. LED replacements are more expensive and are only necessary if your car's system was designed for them from the factory.

Remove the old bulb and install the new one

If you are accessing the light from the boot, locate the plastic cover on the inside of the bumper panel and twist it anticlockwise. It will come free in your hand. You will now see the bulb holder — a small plastic cartridge with the bulb inside. Twist this anticlockwise as well and pull it out gently.

If you are accessing the light from outside, use a flat tool like a plastic trim tool or old credit card to carefully pry the lens cover away from the bumper. Do not use a metal screwdriver, as you can scratch the paint. Once the cover is off, you will see the bulb holder. Twist it anticlockwise and pull it out.

Once the holder is out, the bulb either twists out of the holder or pulls straight out, depending on the type. If it twists, turn it anticlockwise. If it pulls, straightforward pull it straight out. Insert the new bulb the same way — twist clockwise if it twists, or push straight in if it pushes. Do not force it; it should slide in smoothly.

Reinsert the bulb holder into the fixture by pushing it in and twisting clockwise until it stops. Replace the lens cover by twisting it clockwise. Test the light by turning on your headlights or parking lights — the number plate should now be lit.

What to do if the light still does not work

If you have installed a new bulb and the light is still off, the problem is not the bulb. The issue is either a blown fuse, a broken wire, or a faulty fixture. These are not jobs to attempt yourself — you need a mechanic or an auto electrician.

Before you book an appointment, check the fuse box. Your owner's manual shows which fuse controls the number plate light. Open the fuse box (usually under the dashboard or in the engine bay), locate the correct fuse, and look at it. If the wire inside is broken or blackened, the fuse has blown. You can replace it with a new fuse of the same amperage — they cost pennies and are sold at any motor factors. If the fuse blows again when ready after you replace it, there is a short circuit in the wiring and you need a professional.

If the fuse is intact and the bulb is new, the wiring or the fixture itself is faulty. Take the car to a mechanic — this usually takes under an hour to diagnose and repair.

Prevent number plate light failure

Number plate lights fail because the bulb reaches the end of its life, or because water gets into the fixture and corrodes the contacts. You cannot stop a bulb from aging, but you can slow water damage by checking the lens cover for cracks or loose seals. If the cover is damaged, replace it — they cost £5 to £15 and are available from motor factors or online.

Check your number plate light every few months by turning on your parking lights and walking around the car. If it is off, replace the bulb when ready. Catching it early means you avoid a fine and you know the fixture is still working.

Frequently Asked Questions

Can I drive with a broken number plate light?

No. A non-working number plate light is illegal in most places and police can stop you and issue a fine. Replace the bulb as soon as you notice it is out. If you are away from home when it fails, buy a replacement bulb at a petrol station or supermarket and install it in the car park — it takes five minutes.

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

No. Number plate lights run on very low voltage and there is no risk of electric shock. You do not need to disconnect anything. straightforward remove the bulb and replace it.

What if the bulb holder is stuck and will not twist out?

explore gentle pressure and twist slowly — do not force it or you may crack the plastic. If it is truly stuck, spray a small amount of penetrating oil around the base and wait a few minutes. Twist again gently. If it still will not budge, stop and take the car to a mechanic rather than risk breaking the fixture.

Is an LED number plate light better than a standard bulb?

LED bulbs last much longer — often 10,000 hours or more compared to 1,000 hours for incandescent — so you replace them less often. They are brighter and use less power. The downside is they cost more upfront. Use them only if your car was designed for LED from the factory, because some older cars' wiring does not work properly with LED bulbs.

Why does my number plate light keep blowing?

Repeated bulb failure usually means water is getting into the fixture and corroding the contacts, or the wiring has a short circuit. Check the lens cover for cracks or loose seals and replace it if damaged. If the cover is fine, the wiring is faulty and you need a mechanic to inspect it.