Changing a headlight bulb is a 15-minute job you can do yourself with basic tools
Most headlight bulbs fail gradually — you'll notice one side dimmer than the other before it goes dark completely. When that happens, you have two choices: take it to a shop and pay labour costs, or spend 15 minutes doing it yourself. The job is straightforward enough that you don't need special training, though the exact steps depend on your car's make and model.
The real work is figuring out how to access the bulb housing behind the headlight. Some cars let you reach it from inside the engine bay. Others require you to remove the entire headlight assembly first. Once you know the path, the bulb itself straightforward twists or pulls out, and a new one goes in the same way.
Key Takeaways
- Check your owner's manual or search your car's year, make, and model online to find the exact steps for your vehicle, because access routes vary widely.
- Buy the correct bulb type before you start — halogen, LED, or HID — because they are not interchangeable and using the wrong type can damage the housing or create a safety hazard.
- Turn off the engine and let the headlight cool for at least five minutes before touching the bulb, because halogen bulbs get hot enough to burn skin.
- Avoid touching the new bulb with bare fingers if it is halogen, because skin oils cause the bulb to fail prematurely or shatter.
Find your bulb type and get the right replacement
Your car uses one of three headlight bulb types: halogen, LED, or HID (high-intensity discharge). Halogen is the most common in older and mid-range vehicles. LED is standard on newer cars and luxury models. HID is less common but appears on some higher-end vehicles. You cannot swap these types — a halogen bulb will not fit an LED socket, and forcing it will damage both the bulb and the housing.
The easiest way to find your bulb type is to check your owner's manual. Look in the index for "headlight" or "bulb replacement" and it will tell you the exact type and part number. If you don't have the manual, search online for "[your year] [make] [model] headlight bulb type" and you'll find the answer in seconds. Write down the part number or bulb size code — it looks like H7, 9005, or similar — and take it to an auto parts store. Staff can match it to the correct replacement.
Cost varies by type. Halogen bulbs typically run £5 to £15 per bulb. LED bulbs are £20 to £50. HID bulbs are £30 to £100 or more. Buy two if both sides are the same age, because the second one will fail soon after the first.
Locate the headlight housing and access point
Open your bonnet and look at the back of the headlight assembly. You'll see either a plastic or rubber cap covering the bulb socket, or you'll see that the entire headlight unit needs to come out. Your owner's manual will show you which. If the manual is not available, search for a YouTube video of your exact car model — watching someone do it takes 90 seconds and shows you exactly what to expect.
Some vehicles let you access the bulb by reaching behind the headlight from inside the engine bay. Others require you to remove the headlight assembly completely, which usually means unbolting it (typically three bolts) and unplugging the electrical connector. A few cars require removing the wheel well liner or bumper cover first. This is where the manual or a video saves you time and frustration.
If you find that access is genuinely difficult — for example, if the engine bay is so packed that you cannot reach the bulb housing — this is a legitimate reason to take the car to a shop. Some vehicles are straightforward not designed for owner maintenance of this part.
Remove the old bulb safely
Turn off the engine and wait at least five minutes. Halogen bulbs reach temperatures above 200°C when lit, and touching one when ready after it goes dark will burn your skin. While you wait, put on safety glasses — this protects your eyes if the old bulb is cracked or if debris falls from the housing.
Once the bulb is cool, locate the socket. It will either twist counterclockwise (like a light bulb in a lamp) or pull straight out. Try twisting first — most automotive bulbs twist. If it does not move after gentle pressure, it pulls out instead. Do not force it either way. If you meet real resistance, stop and check your manual again, because you may be turning the wrong part.
When the socket comes free, the bulb will either stay in the socket or come out with it. If it stays in the socket, grip it gently and pull it straight out. Set the old bulb aside — do not throw it away yet, because you may need to return it to the shop if the new one is defective.
Install the new bulb and test it
If the new bulb is halogen, do not touch it with bare fingers. Skin oils cause the bulb to overheat and fail within weeks, or to shatter while lit. Wear clean cotton gloves, or hold the bulb by its plastic base only. If you have already touched it, wipe it clean with a lint-free cloth before installation.
Insert the new bulb into the socket. It will either slide in and twist clockwise until it stops, or push straight in until it seats. Use the same motion you used to remove the old one. Do not force it — the bulb should seat smoothly with gentle pressure. Once it is in, reattach the socket to the headlight housing by reversing the removal steps (twist clockwise, or push until it clicks).
If you removed the entire headlight assembly, plug the electrical connector back in and bolt the assembly back to the car. Tighten the bolts firmly but do not over-tighten, because you can crack the plastic housing.
Check that both headlights work before you drive
Close the bonnet and sit in the driver's seat. Turn on the headlights and look at the front of the car. Both lights should be equally bright. If the new bulb is dim, or if it does not light at all, turn off the headlights and wait a moment. Some LED bulbs take a few seconds to reach full brightness. If it still does not work after 30 seconds, the bulb may be defective or you may have installed it incorrectly.
If the bulb is not working, remove it and check that it is seated fully in the socket. Reinsert it and test again. If it still fails, the bulb is likely defective — take it back to the shop with your receipt and exchange it for another one. Do not drive with one headlight out, because it is unsafe and illegal in most places.
When to take the car to a shop instead
Some headlight jobs are genuinely difficult and not worth doing yourself. If the access route requires removing the bumper, wheel well liner, or other major components, a shop can do it faster and with less risk of breaking something. If the headlight housing is cracked or the socket is damaged, the bulb will not stay in place — this requires professional repair.
If you are uncomfortable working in the engine bay, or if you have tried and cannot figure out how to access the bulb, there is no shame in taking it to a shop. Labour costs typically run £30 to £80 depending on the vehicle and the shop's rates. That is money well spent if it means you avoid damaging something else in the process.
Frequently Asked Questions
Can I use a different bulb type than the one my car came with?
No. The socket, wiring, and reflector are all designed for a specific bulb type. Using the wrong type can damage the housing, create a fire hazard, or blind oncoming drivers. Stick with the type listed in your manual.
Why does my new headlight bulb keep burning out?
If a halogen bulb burned out quickly, you may have touched it with bare fingers during installation — skin oils cause premature failure. If an LED bulb is failing, the housing or wiring may be damaged, or the bulb itself may be defective. Take it back to the shop and describe what happened.
Do I need to replace both headlight bulbs at the same time?
Only if both are failing. If one bulb is dark and the other is bright, replace only the dark one. If both are equally dim, they are aging together and replacing both now will save you a second trip later.
What if the bulb socket is stuck and won't turn or pull out?
Stop when ready — forcing it can break the socket or the housing. Spray a small amount of penetrating oil (like WD-40) around the base of the socket, wait 10 minutes, and try again gently. If it still will not move, take the car to a shop rather than risk damage.
Is it safe to drive with one headlight out?
No. It is unsafe because you have reduced visibility and oncoming drivers may not see you clearly. It is also illegal in most places — you can be stopped and fined. Replace the bulb or have it replaced before driving at night.