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

Honda CR-V prices slashed by thousands, ZR-V gets cheaper too
2026 Honda CR-V - front cornering

Honda CR-V prices slashed by thousands, ZR-V gets cheaper too

Honda has revealed updated pricing for the CR-V and ZR-V models, with the latter getting a particularly chunky discount
News
2 Nov 2026
New Renault Megane to take on the Tesla Model Y with a radical makeover
Renault Megane - front quarter exclusive image Avarvarii

New Renault Megane to take on the Tesla Model Y with a radical makeover

Hi-tech ‘software-defined’ C-segment model heralds a new design direction for Renault as the firm works to achieve a 465-mile range
News
2 Nov 2026
New Fiat Topolino Dolcevita arrives as dinky electric convertible for £9,500
Fiat Topolino Dolcevita - front 3/4

New Fiat Topolino Dolcevita arrives as dinky electric convertible for £9,500

The cute electric quadricycle can now be ordered as a convertible for a small additional outlay
News
3 Nov 2026

Find a car with the experts