The H11 bulb is a single-filament 12V halogen bulb with a PGJ19-2 base, primarily used for low-beam headlights and fog lights in US-market vehicles.
If your low beams are dimming or one burned out, the replacement under your hood is likely an H11. It’s one of the most common automotive bulbs on the road, found in everything from sedans to full-size trucks. But the H11 family includes LED upgrades and interchangeable siblings, so knowing which one fits and where it works matters more than grabbing the cheapest pack.
What Makes an H11 Bulb Unique
The H11 runs on a 12V system, draws 55 watts standard, and produces about 1,350 lumens at a 4,000K halogen color. Its single-filament design means it handles only one beam function per bulb—most commonly low beams, but also fog lights and daytime running lights (DRLs). The defining physical feature is the L-shaped PGJ19-2 plastic base with three locking spurs, one of which is wider. That shape prevents accidental installation into the wrong socket.
Which Bulbs Are Interchangeable With H11
The H11 shares its socket and connector with three other bulbs: H8, H9, and H16. They all fit the same housing, but wattage varies significantly.
| Bulb Type | Standard Wattage | Typical Lumens | Common Use |
|---|---|---|---|
| H11 | 55 W | 1,350 | Low beams, fog lights |
| H8 | 35 W | 800 | Fog lights |
| H9 | 65 W | 2,100 | High beams |
| H16 | 19–25 W | 500 | Fog lights |
Using a 55W H11 in a housing designed for a 35W H8 fog lamp can melt the socket or wiring, so check your owner’s manual for the correct wattage rating before swapping. If you’re considering an upgrade, our tested roundup of the best H11 LED bulbs for brightness and fit covers the top performers.
Installing an H11 Bulb
Replacing an H11 takes about ten minutes. Park on level ground, switch off the lights, and open the hood to access the back of the headlight assembly. Reach behind the housing, turn the old bulb counterclockwise to release the base, then gently unplug the wiring harness. Align the three spurs on the new PGJ19-2 base and turn clockwise until it locks. Reconnect the harness until it clicks, then test both low beams before closing the hood.
Common mistakes include jamming an H11 into a high-beam socket—the prongs won’t align, and forcing them cracks the connector—or buying an H11B, which has a different PGJY19-2 base that won’t lock into an H11 housing.
Common Questions About H11 Bulbs
FAQs
Can I use H11 bulbs for high beams?
No. H11 is a single-filament bulb designed for low beams only. For high beams, you need a bulb like the H9 or a dedicated dual-filament type such as H4. Installing an H11 in a high-beam socket risks poor beam pattern and electrical issues.
How long do H11 halogen bulbs last?
Quality units from SYLVANIA or OSRAM tend toward the longer end, while high-output 100W variants burn hotter and have shorter lifespans.
What is the difference between H11 and H11B?
The H11 and H11B share the same electrical specs but use different bases. H11 uses a PGJ19-2 plastic base, while H11B uses a PGJY19-2 base with a slightly different locking pattern. They are not interchangeable, so check your vehicle’s specification before buying.
References & Sources
- Wikipedia. “List of automotive light bulb types.” Covers H11 specifications, base types, and interchangeability with H8, H9, H16.
- OSRAM. “ORIGINAL LINE Halogen headlight lamps.” Official product page for standard H11 halogen bulbs.
- SYLVANIA. “SYLVANIA SilverStar ULTRA H11 headlight bulb.” Product details including wattage, lifetime, and fitment.