LED headlights are brighter, whiter and longer-lasting than halogen headlights and use less power, which is why most new vehicles now use them. Halogen headlights are inexpensive and work as designed in the housings built for them. The catch with upgrading is the housing: an LED bulb placed in a reflector or projector built for a halogen bulb often scatters light, causing glare for other drivers and dark spots on the road, and in the US such replacement bulbs are generally not certified for road use. Complete headlight assemblies designed for LED light sources avoid that problem.
LED vs halogen headlights
| Halogen | LED | |
|---|---|---|
| Light color | Warm, yellowish white | Cool, bright white |
| Brightness | Lower | Higher |
| Life | Shorter | Much longer |
| Power use and heat | More power, hot glass | Less power, heat at the base |
| Cost | Low | Higher |
Are aftermarket LED headlights legal?
In the US, headlights must meet federal lighting standards as a complete lamp. LED replacement bulbs in housings designed for halogen bulbs are generally not certified for road use, and states may enforce this at inspection. Complete aftermarket headlight assemblies may carry their own compliance information; check the listing and your state’s rules before installing any lighting upgrade.
Housing matters more than the bulb
Projector housings control light with a lens and cutoff, while reflectors depend on the light source sitting exactly where the halogen filament was; see projector vs reflector headlights. That is why a complete LED headlight assembly, built around LEDs, usually performs better than a bulb swap.
Complete LED headlight assemblies
For the 2015 to 2021 WRX and STI, we list the Molded Innovations Odyssey sequential LED headlights for the WRX and STI at $934.99; check the listing for fitment by trim and its details. See Subaru WRX and STI parts.
Why LED light looks brighter
LED light is whiter and closer to daylight, which makes signs and road edges look sharper. Whether that translates into better visibility depends on the beam pattern: a well-designed beam puts light down the road and to the edges without spilling into oncoming drivers’ eyes.
Heat and moisture
LEDs need their heat drawn away from the base, which is why LED headlights use heat sinks or fans. Halogen bulbs run hot at the glass, which helps clear moisture from the lens. That difference is one reason some LED-converted housings fog up; see headlight condensation.
After any headlight change
Aim the headlights so the beam does not blind oncoming drivers; see how to adjust headlights. Moisture inside a new assembly is covered in headlight condensation.
Which should you choose?
- Keep it simple and inexpensive: quality halogen bulbs in the factory housing.
- Want LED light: a complete LED headlight assembly made for your vehicle.
Shipping is a flat $80.00 per order to US addresses, with 15-day free returns. Questions? Ask a parts specialist.