Are H11 and 9005 Headlights the Same?

No. H11 and 9005 are different bulb types with distinct bases, power ratings, and typical uses, so they are not directly interchangeable. H11 is commonly used for low beams and fog lights, while 9005 (also called HB3) is typically used for high beams; attempting to swap them without proper housings or adapters can cause poor light aim, glare, or legal issues.

What Each Bulb Is Designed For

Automotive halogen bulbs are standardized by fitment, wattage, and optical design. H11 and 9005 serve different roles in many factory lighting systems, and their connectors and bases are keyed to prevent accidental cross-installation.

H11 at a glance

H11 is a single-filament halogen bulb often specified for low beams or fog lamps. It uses an H11-specific keyed base (commonly referenced as PGJ19-2), draws about 55W at 12.8V, and produces roughly 1,250–1,350 lumens in standard form. It’s widely used in projector low-beam assemblies and fog housings where controlled cutoff and reduced glare are critical.

9005 (HB3) at a glance

9005, also known as HB3, is a single-filament halogen bulb usually used for high beams (and sometimes as DRLs in North America). It uses the HB3/900x family base, draws about 65W at 12.8V, and outputs around 1,700 lumens. High-beam optics prioritize distance reach and intensity over the strict cutoff needed for low beams.

Key Differences That Matter

The distinctions between H11 and 9005 go beyond naming—they affect fitment, performance, and legality. The following points outline where they diverge and why that matters when maintaining or upgrading headlights.

• Base and socket: H11 uses an H11-specific keyed base (PGJ19-2), while 9005/HB3 uses the 900x/HB base family; they do not lock into each other’s housings without adapters or modifications.
• Typical application: H11 is commonly low beam or fog; 9005 is commonly high beam and sometimes DRL. The optics in each housing are designed around that role.
• Power and output: H11 is about 55W with roughly 1,250–1,350 lm; 9005 is about 65W with roughly 1,700 lm. Swapping can overheat housings not designed for higher wattage or produce the wrong beam pattern.
• Connector and pins: The electrical connectors are keyed differently and generally won’t mate without a purpose-made harness.
• Beam pattern and safety: A bulb designed for high-beam optics used in a low-beam housing (or vice versa) can cause severe glare, poor road illumination, and fail inspections.
• Variants: Some vehicles use H11B (a different keyed connector) instead of standard H11, further limiting interchangeability. The 900x family also includes 9006 (HB4) and others with different roles and bases.
• LED “equivalents”: Aftermarket LED kits often list multiple “cross-fit” numbers, but the base type must still match the housing; cross-listing does not mean physical or legal compatibility.
• Regulatory compliance: In many regions (including the U.S.), LED retrofit bulbs for halogen headlamp housings are not street-legal unless specifically certified; compliance varies by jurisdiction.

Taken together, these differences mean H11 and 9005 are engineered for distinct sockets and optics, and swapping typically leads to fitment problems and unsafe or noncompliant lighting.

Can You Swap Them With Adapters?

Direct swaps are not recommended. While some aftermarket adapters and wiring harnesses exist, they don’t change the fundamental optical and thermal design of the headlamp. Even if you can physically fit or power the bulb, the beam pattern and heat management may be wrong for the housing.

1. Check the owner’s manual or the bulb label on the headlamp housing for the exact bulb type specified (e.g., H11, H11B, 9005/HB3).
2. Confirm the role (low beam, high beam, fog) and use the bulb engineered for that role and housing.
3. If upgrading output, consider higher-performance halogen options of the same base (e.g., premium +% output halogen) that maintain compliance and proper optics.
4. If considering LED or HID conversions, verify legal status in your region and choose a kit explicitly designed and certified for your housing type; otherwise, keep it to off-road use.
5. For vehicles with both H11 (low) and 9005 (high), upgrade each position with its proper matching bulb rather than trying to cross-fit.

These steps help ensure you maintain correct aim, avoid glare, prevent overheating, and stay within local regulations while improving performance safely.

Buying and Fitment Tips

To avoid returns and ensure safe, effective lighting, pay attention to the exact bulb specification and quality of parts. These quick checks can keep your upgrade straightforward and compliant.

• Match the base exactly: H11 to H11 (or H11B if specified), 9005 to 9005/HB3—don’t rely on “will fit” claims alone.
• Consider reputable brands: Established OEM and aftermarket brands tend to meet lumen, color, and lifespan specs more reliably.
• Avoid excessive color temperatures: Very blue “look” often reduces usable light on wet roads and may attract legal scrutiny.
• Replace in pairs: Especially for low beams, replacing both sides keeps color and brightness consistent.
• Inspect housing condition: Cloudy lenses or damaged reflectors can negate any bulb upgrade; restore or replace as needed.

Following these guidelines preserves beam quality and ensures your lighting system performs as designed under real-world conditions.

Bottom Line

H11 and 9005 are not the same and are not meant to be swapped. Use the bulb type specified for your vehicle’s headlamp or fog lamp position. If you want more light, choose higher-performance bulbs of the correct base or a compliant, housing-specific upgrade rather than mixing types.

Summary

H11 (typically low beam/fog) and 9005/HB3 (typically high beam) differ in base design, wattage, output, and intended optics. They are not directly interchangeable, and attempts to cross-fit can produce unsafe glare, poor visibility, overheating, or legal issues. Always match the bulb to the specified socket and role, and pursue upgrades that maintain proper optics and compliance.

Do H11 and 9005 have the same connector?

You cannot fit a 9005 (HB3) into an H11 headlight. You also cannot fit an H11 into a 9005 (HB3) headlight. As explained in previous sections, each bulb has its unique locking tabs, plugs, and size which make them incompatible and not interchangeable.

Which bulb is the same as 9005?

What Bulb Is Equivalent to HB3 and 9005? The HB3 and 9005 bulbs are equivalent, along with several other bulb sizes: H10, 9040, 9055, 9140, 9145, 9150, and 9155. They share the same base design and can be used interchangeably in most cases.

Can you use 9005 instead of H11?

Compatibility: While primarily used for high beams, 9005 bulbs can also be found in some low-beam and fog light applications. However, H8 and H11 are more likely to be in fog lights. Remember, these lights have distinct housings and wiring connectors. So, you can’t simply swap an H11 with a 9005 bulb.