Are 9006 and H11 Headlight Bulbs the Same?

No—9006 and H11 are not the same, and they are not plug‑and‑play interchangeable. While both are single‑beam 12V halogen bulb types commonly rated around 55W, they use different bases, connectors, and locking tabs. For safety, performance, and legal compliance, you should use the exact bulb type specified by your vehicle.

What Each Bulb Designation Means

9006 (also called HB4)

The 9006, known in standards as HB4, is a single‑beam halogen bulb widely used in North American vehicles for low beams and fog lamps. It typically runs at 12.8V/55W and uses a P22d base with a square‑profile plastic connector. Its geometry, locking tabs, and filament position are defined by the SAE/ANSI HB standard family.

H11

H11 is a single‑beam halogen bulb common in global markets for low beams and fog lamps. It typically runs at 12.8V/55W and uses a PGJ19‑2 base with a different tab layout and a round keyed connector. Its dimensions and focal position are defined by ECE regulations for the H‑series family.

Key Differences at a Glance

The distinctions between 9006 and H11 matter for fit, beam focus, and electrical connection. The following points highlight the practical differences drivers encounter when selecting or replacing bulbs.

• Base and connector: 9006 uses a P22d base with a square, two‑pin plug; H11 uses a PGJ19‑2 base with a keyed round two‑pin plug. They do not physically mate.
• Locking tabs and indexing: The tabs that secure the bulb in the housing are shaped and positioned differently, so each bulb aligns uniquely in its intended socket.
• Focal position: The designed filament location relative to the mounting plane differs by standard, which affects beam pattern if the wrong bulb is used.
• Applications: Both serve low beam and fog roles, but housings are engineered around the specific bulb family’s geometry and optics.
• Electrical interface: Both are two‑wire 12V bulbs around 55W, but connector keying and pin orientation differ; adapters are required to cross-connect, and polarity must be correct.
• Output characteristics: Light output specs and permissible tolerances are set by different standards bodies, so performance and beam control are not equivalent across families.
• Compliance: Swapping across families can violate DOT/SAE or ECE compliance and may create glare or insufficient roadway illumination.

Taken together, these differences mean a 9006 will not properly fit or function in an H11 socket (and vice versa) without modification—and even then, beam quality and legality can suffer.

Can You Swap Them?

Not directly. A 9006 bulb will not plug into an H11 harness or lock into an H11 housing, and an H11 will not fit a 9006 setup. Some enthusiasts use adapters or minor trimming, but this is not recommended because it can compromise beam focus, cause glare, damage wiring, or void compliance.

• Harness adapters: H11‑to‑9006 pigtail adapters exist for custom projects, but they only address the electrical plug—mechanical fit and optical focus remain problems.
• Tab trimming: Filing tabs to “make it fit” risks misalignment, poor sealing, moisture intrusion, and incorrect beam aim.
• Housing changes: Swapping the entire lamp housing to one designed for the other bulb type is the proper way to change families, but it’s more involved and must remain road‑legal.
• LED kits: LED replacements are sold in both bases (H11 and 9006). You must choose the correct base for your socket; using the wrong base with an adapter rarely yields proper beam patterns.

If you need a brighter or different‑color output, stick to upgrades within your bulb family (for example, premium H11 halogens for H11 housings) to preserve optical performance and compliance.

How to Confirm the Correct Bulb for Your Vehicle

To avoid misfit parts and degraded lighting, verify what your car actually requires. The following steps help ensure a correct and safe selection.

1. Check the owner’s manual: Look up the exact bulb type for low beam, high beam, and fog lights.
2. Inspect the existing bulb: The type is usually printed on the bulb base (e.g., “H11,” “9006”).
3. Use an OEM parts catalog or VIN lookup: Manufacturer databases list the correct specification for your trim and market.
4. Read housing markings: Many headlamp housings are labeled with approved bulb types.
5. Match beam function: Ensure you’re replacing like‑for‑like (low beam vs. high beam vs. fog).
6. Avoid mixing bulb families: Do not substitute H‑series bulbs into HB‑series sockets (or vice versa).
7. Test fit and aim: After installation, verify secure locking, weather seal, and beam cutoff on a wall to confirm proper focus.

Following these checks will help you maintain the intended lighting performance and prevent electrical or optical issues.

Related Bulb Families and Near‑Equivalents

When planning upgrades, it helps to know which bulbs are part of the same family and which are not. This can reveal safe, higher‑performance options without crossing standards.

• 9006 family: 9005 (HB3) is the related high‑beam type but uses a different base; 9012 (HIR2) is a higher‑efficiency option with a similar footprint to 9006 that may fit certain 9006 housings when specified by the manufacturer.
• H11 family: H8 and H16 share the same base family with different wattage/heat ratings; H9 offers higher output but requires careful consideration of heat and housing compatibility.
• Cross‑family caution: H11 and 9006 are from different standards families (H vs. HB) and are not direct substitutes.
• HID and LED: HID “D‑series” and many LED retrofit systems are different technologies and must match the housing and base to maintain beam control and legality.

Staying within the intended bulb family is the most reliable way to improve performance without sacrificing safety or compliance.

Summary

9006 (HB4) and H11 are not the same and are not directly interchangeable. They use different bases, connectors, and optical geometries, and swapping them can impair beam pattern and legality. Always use the bulb type specified for your vehicle, and pursue upgrades within the same bulb family to preserve safe, compliant lighting performance.

What is H11 interchangeable with?

An H11 bulb is the same as an H8, H9, and the L-shaped H16 (Type A), meaning they share the same base, shape, and connector, though they may have different standard wattages or applications (like H11 for low beams and H8 for fog lights). While H11 bulbs can often be used interchangeably with H8 or H9, it’s crucial to check your vehicle’s owner’s manual or use a bulb finder tool, as wattage and fitment can vary.
 
Similarities:

• Base and Connector: H11, H8, H9, and H16 bulbs share the same physical base and connector, allowing for fitment in the same sockets. 
• Single Filament: All are single-filament bulbs, meaning they provide one type of light. 
• Technology: They are all available in standard halogen, as well as LED and HID upgrade options. 

Differences:

• Wattage and Application:
  • H11: is commonly a 55-watt bulb used for low beams. 
  • H8: is often a lower-wattage bulb, typically 35 watts, found in fog lights. 
  • H9: is a higher-wattage bulb, around 65 watts, suitable for high beams. 
• H16 Type: There are two types of H16 bulbs; the H16 Type A (Japanese version) is the L-shaped equivalent to the H11, while the H16 Type B is a different, T-shaped bulb found in American vehicles. 

Key takeaway: While H11, H8, and H9 share a physical form, their original wattage and intended use can differ. For LED or HID upgrades, the wattage differences become less relevant, but it is still essential to verify the correct bulb for your specific vehicle.

Can you use 9006 instead of H11?

No, you cannot directly use a 9006 bulb in place of an H11 bulb, and vice versa. While both are used as low-beam headlights in some vehicles, they have different base types, locking tabs, and connector designs, making them physically incompatible. 
Here’s why they are not interchangeable:

• Base Differences: H11 and 9006 bulbs have different base types, meaning the way they connect to the headlight socket is not the same.
• Locking Tabs: The locking tabs that secure the bulb in place are different in size and position for H11 and 9006 bulbs.
• Connectors: The connectors (plugs) that attach to the vehicle’s wiring harness are also different, with the H11 having narrower prongs than the 9006.
• Size: H11 bulbs are generally smaller than 9006 bulbs. 

While you might find ways to modify the wiring or socket to make them fit, it is not recommended as it can lead to poor electrical connections, improper light projection, and potentially damage the headlight assembly or the bulb itself. It’s always best to use the bulb type specified for your vehicle’s make and model.

What bulb is the same as 9006?

For instance, 9006 is the same as 9012 and HB4. All three of these bulbs have the exact same locking tabs, wiring, and plugs. H11 and 9005, on the other hand, are not the same.

What is the difference between H11 and 9006 sockets?

The main difference between the two bulbs is that the H11 connector has two narrow set prongs separated by a plastic tab compared to the 9006, which has two wide set prongs. The H11 connector is also smaller than the 9006 and has tiny plastic tabs on each side of the plug casing.