One of the most common bulbs used in headlamps in UK cars since the 1970s is the ubiquitous H4. Today's new cars are generally fitted with LED or Xenon headlights, but halogen bulbs can still be found on around 80% of cars. They give a high-intensity yellow-white light and are very cheap to produce. The H4 bulb was designed to provide low and high-beam functions in a single unit, using a dual-filament design with one filament for each beam. When it was launched, it was a more convenient and cost-effective way of producing vehicle lighting compared to earlier systems that required separate bulbs for low and high beams within the same housing.
The H4 quickly gained popularity as it was versatile and provided a good balance between low and high-beam functions. It was compatible with various vehicles and manufacturers, so it was widely adopted across the UK and Europe. The H4's standardized design also facilitated its use in different car models, further enhancing its popularity among manufacturers and consumers alike.
Best H4 bulbs at a glance:
Editors choice: Philips GT200 - Buy now from Amazon UK
Best for contemporary look: Osram Cool Blue Intense - Buy now from Amazon UK
Best for budget: Lucas LLB472 H4 Pair - Buy now from Amazon UK
The H4 bulb has been successful for a few decades now and despite there being a gradual shift towards new lighting technologies like HID bulbs that offer better light efficiency and brightness, it will be some time before the H4 bulb is replaced as a mainstay of car lighting. So, let's take a look at some of the best H4 bulbs available.
Find the correct bulbs for your vehicle
Via AmazonMake sure you order the correct bulbs for your vehicle by inputting your registration number into the Amazon Garage.
Pros
- Great choice of bulbs
- Easy to select the correct bulbs for your car
Cons
- Amazon Prime needed for free delivery
Editor's choice
These Philips Racing Vision GT200s have been developed using new bulb coating techniques to deliver high-performance light using new quartz glass technology for ultra-precise light output and a beam that illuminates a further 80m of the road ahead. The higher light output does mean that the lifespan may be a bit less than that of a traditional H4 bulb.
Pros
- Sharp image
- More light
Cons
- Shorter lifespan
Best for brightness
The Night Breaker series from Osram has been developed to deliver impressive output thanks to an innovative laser ablation technology that allows these headlight bulbs to shine up to 130% brighter than standard halogen lamps. The H4 version gives a more contemporary, whiter light than a standard halogen bulb. There is a slight downside, which is that due to its greater power output, its lifespan may not be as long as a standard bulb.
Pros
- Whiter light
- Longer beam
Cons
- Lifespan could be a bit shorter than standard bulbs
Best for long life brightness
www.halfords.com
The Halfords Advanced H4 bulb is a great upgrade for your headlight system. It's a direct replacement for a standard H4, but it gives a whiter light and up to 200% more light on the road without any compromise on the lifespan of the bulb.
Pros
- Whiter, more powerful light
- No compromise on lifespan
Cons
- No blue tint
Best Xenon lookalike
The colour temperature of these Bosch units is 4200K which means the light emitted is moving away from the yellow spectrum providing a whiter light than normal halogen bulbs, so they will give your lights a slightly more contemporary look as well as deliver extra brightness. With an appearance similar to daylight, this intense white light brings an aesthetic touch to your vehicle and gives a relaxed and comfortable driving experience at night or in bad weather.
Pros
- Xenon lookalike
- Extra bright
Cons
- Shorter lifespan
Best contemporaty look
The Osram Cool Blue Intense bulbs offer the LED look at a great value price. The colour temperature of this set is 5,000K, so you are moving away from yellow light towards blue light. You get a contemporary look and an increase in brightness to improve your nighttime and poor weather vision.
Pros
- Contemporary look
- Good value
Cons
- Not quite a blue light
Best single pack
www.halfords.com
The Ring Pro is a direct replacement for your factory-fitted H4 bulb, providing a precise beam pattern and excellent illumination but with the added benefit of having a longer lifespan. Ring says this bulb will last up to 50% longer than standard H4 bulbs, and it comes at a pretty competitive price, too.
Pros
- Direct OEM replacement
- Long lifespan
Cons
- No improvement to standard illumination
Best for budget
There is more good value in this pair of bulbs from Lucas. You'll find improved brightness over a standard halogen bulb, and then there's the peace of mind afforded by the Lucas name. You won't find any blue tints with these bulbs, just a nice crisp white to illuminate your way in the night.
Pros
- Good value two pack
- Improved brightness
Cons
- No contemporary look
Some frequently asked questions:
What are H4 bulbs used for?
H4 bulbs have a dual filament, one for low beam and one for main beam, enclosed within a single glass housing.
What is the average lifespan of an H4 bulb?
An H4 bulb will last between 400 and 900 hours depending on use, road conditions and other variables like temperature.
Are H4 bulbs brighter than other options available?
While H4 bulbs are effective, newer technologies like LEDs and HIDs often provide brighter and more focused light output, potentially offering better visibility on the road.
Can I upgrade my H4 bulbs to LEDs or HIDs?
Yes, many vehicles can be upgraded to HID or LED headlights. However, this might involve modifications and could affect the beam pattern or may not be legal in some cases. It's advisable to check regulations and compatibility before upgrading.
Are H4 bulbs energy-efficient?
H4 bulbs are generally less energy-efficient than LEDs, which consume less power and produce less heat. Upgrading to LEDs could result in energy savings in the long run.
_Alex Boyd _is a Commercial Content Writer at CAR and Parkers and loves travel, gardening, DIY and music.__