LED headlight bulb retrofits: UK vs US vs Germany vs Norway
Dropping an LED bulb into a housing designed for a halogen filament is the most commonly sold illegal modification in this list. One of these four markets built an approval route for it; the rest did not.
The verdict is not the same in all four markets, so the column that matters to you depends on where the car is registered.
| Market | Verdict | The rule that decides it |
|---|---|---|
United Kingdom DVSA / GOV.UK |
Not legal | No type approval exists for retrofit bulbs On cars first used from April 1986, a headlamp whose light source does not match its approval fails the test. A complete e-marked LED headlamp unit is fine. |
United States EPA, NHTSA and state codes |
Not legal | No DOT-compliant conversion bulb exists Federal lighting standard FMVSS 108 governs the assembly, and a retrofit bulb in a reflector housing does not meet it. Factory LED systems are unaffected. |
Germany StVZO / KBA |
Conditional | Legal only with an ABG for your exact car and lamp The bulb maker publishes a KBA approval list, and only the vehicle and headlamp combinations named on it are permitted. The paperwork travels in the car. |
Norway Statens vegvesen |
Not legal | Breaks the headlamp type approval The lamp is approved as a unit together with its light source, so a swapped source is a standard inspection remark. Check documentation carefully on any model-specific kit. |
Germany is the outlier, and only because it created a bulb-level approval scheme with a published compatibility list. Elsewhere the answer is a complete approved headlamp unit, not a bulb.
Why the answers differ
Can you put LED bulbs in halogen headlights?
The disagreement here is not about whether LED light is acceptable, it is about the unit of approval. The US and Norway both approve the headlamp as a complete assembly including its light source, so changing the source breaks the approval by definition and no bulb can ever be compliant on its own. The UK reaches the same place by a different route: no type approval exists for a retrofit bulb, so a lamp whose source does not match its approval fails. Germany is alone in creating a bulb-level approval, which means a specific bulb can be certified for a specific headlamp on a specific car, published on a list. That is genuinely more permissive, but it is also much narrower than it sounds, because a bulb approved for one car is not thereby approved for another.
Verdict at a glance
The same four markets, grouped by where they land.
Conditional
ConditionalGermany. Permitted, but only once the condition in the table above is met.
Not legal
Not legalUnited Kingdom, United States and Norway. No approval route exists for road use. Any offer of a compliant version is worth checking carefully.
Sources
Primary legislation and regulator guidance behind each market's verdict.
- UKRoad Vehicles Lighting Regulations 1989
- UKMOT inspection manual: 4. Lamps, reflectors and electrical equipment (GOV.UK)
- USFederal Motor Vehicle Safety Standards, lighting (NHTSA)
- USVehicle modifications and equipment (NHTSA)
- Germany§ 22a StVZO - Bauartgenehmigung für Fahrzeugteile (gesetze-im-internet.de)
- Germany§ 50 StVZO - Scheinwerfer für Fahrlicht und für Abblendlicht (gesetze-im-internet.de)
- Germany§ 49a StVZO - Lichttechnische Einrichtungen (gesetze-im-internet.de)
- NorwayKjøretøyforskriften kap. 28 - Lys og lyssignal (lovdata.no)
Other cross-market comparisons
This is a comparison of national rules, not legal advice for your vehicle. Rules change, and the US row in particular summarises federal law where one exists and the common pattern across states where it does not. Confirm the position in your own state or region before you buy or fit anything. Sources last reviewed July 2026.