Skip advert
Advertisement

What are halogen headlights and how do they work?

We explain what halogen headlights are and how they work to keep you safe at night

Halogen headlights are named after a group of gas elements (the halogens) which are used inside them. In a bulb, the primary function of a halogen gas is extend the life of the tungsten filament – but more on that later.  

They aren’t just popular in the automotive world, however, as they have been used in homes and street lamps for over half a decade. That said, non-directional household halogen light bulbs are now banned in the EU due to their poor energy efficiency when compared to LED bulbs.

Advertisement - Article continues below

Best headlight bulbs

How do halogen lights work?

Halogens are one of the oldest types of bulbs you would expect to find on a new car sold in the UK. They work in a similar fashion to bulbs you would have seen in houses during the black and white times, meaning they consist of a glass bowl, filament and gas, and when current is passed through the filament it gives off light (and a large amount of heat).

They are called halogens as halogen gas is used to help prevent the tungsten filament being dumped on the glass and blackening the surface of the glass – meaning the bulb stays brighter for longer.

Halogen lights pros and cons

Pros

  • • Cheap
  • • Easy to replace in the event of failure

Cons

  • • Poor energy efficiency, impacting economy
  • • Life cycle not as long as LEDs are predicted to last

Enjoyed this tips and advice article? Then take a read of our piece investigating night time driving glasses.

Skip advert
Advertisement
Skip advert
Advertisement

Most Popular

New Nissan Juke to get wild design as it goes all-electric
Nissan Juke - front (exclusive image)

New Nissan Juke to get wild design as it goes all-electric

The new Nissan Juke is set to arrive in the UK in 2026, and our exclusive images preview how it could look
News
24 Nov 2025
New Dacia C-Neo preps for its big family car fight in 2026
Dacia C-Neo - front cornering

New Dacia C-Neo preps for its big family car fight in 2026

Romanian firm looks ready to take on a new sector with all-new petrol-powered family car
News
24 Nov 2025
Tesla Model 3 vs Mercedes CLA: which EV is the elite executive car?
Mercedes CLA and Tesla Model 3 - front tracking

Tesla Model 3 vs Mercedes CLA: which EV is the elite executive car?

On paper, Mercedes’ CLA Mk2 looks set to deliver the goods in the electric company-car sector. Has the big-selling Tesla Model 3 finally met its match…
Car group tests
22 Nov 2025