Are 9004 and 9005 Bulbs the Same?

No. 9004 and 9005 headlight bulbs are different in design, socket, and function, and they are not interchangeable. The 9004 (HB1) is a dual‑filament bulb for combined low/high beams, while the 9005 (HB3) is a single‑filament bulb typically used for high beams only. Mixing them can lead to improper fit, incorrect beam patterns, or electrical issues.

What Each Bulb Is

The 9004, also known by its SAE designation HB1, is a dual-filament halogen bulb designed to provide both low and high beams from a single bulb. It uses a three-prong, straight-in connector and was common on many North American vehicles from the late 1980s through the 1990s.

The 9005, designated HB3, is a single-filament halogen bulb typically used as a dedicated high beam (and sometimes as a daytime running light in certain vehicles). It uses a right-angle, two-prong connector and is not designed to provide a low-beam function.

Key Differences at a Glance

The points below outline the most important distinctions between 9004 and 9005 bulbs to help you identify what will work in your vehicle.

• Filament configuration: 9004 is dual-filament (low and high beam); 9005 is single-filament (high beam only).
• Connector and base: 9004 uses a straight, three-prong base; 9005 uses a right-angle, two-prong base. They do not plug into the same socket.
• Typical application: 9004 serves combined low/high-beam headlamps; 9005 is usually a dedicated high beam.
• Optical design: The filament position and focal geometry differ, so housings are engineered specifically for each type to control beam pattern and glare.
• Interchangeability: They are not cross-compatible without improper modifications, which can cause poor light aim, glare, or electrical problems.

Taken together, these differences mean a 9005 cannot substitute for a 9004 (and vice versa) without compromising safety, legality, or function.

Compatibility and Replacement Advice

Because the sockets and functions differ, forcing the wrong bulb type can damage connectors, defeat your low-beam function, or create hazardous glare for other drivers. Always replace bulbs with the exact type your vehicle specifies.

Use the following guidelines to ensure a correct and safe replacement.

1. Verify the part your vehicle requires in the owner’s manual or a trusted bulb lookup by year/make/model/trim.
2. Match the designation and function: 9004 (HB1) for dual-beam housings; 9005 (HB3) for dedicated high-beam positions.
3. Avoid “tab-trimming” or adapters to force-fit another type; this often leads to misalignment, overheating, or wiring stress.
4. If upgrading to LED or HID, use kits specifically engineered for your bulb type and housing, and confirm road legality in your region.

Following these steps helps preserve intended beam pattern, electrical safety, and compliance with lighting regulations.

Specifications Overview

While exact figures vary by brand and standard, the general characteristics below reflect how these bulbs are typically configured and used.

• 9004 (HB1): Dual-filament for low/high beams; commonly around 45W (low) and 65W (high); straight-in, three-prong connector; used where one bulb handles both beams.
• 9005 (HB3): Single-filament, typically around 65W; right-angle, two-prong connector; used primarily as a high beam (and sometimes DRL).

Both are 12V halogen bulbs with a warm white output typical of OEM halogen lighting; however, their physical and optical designs are not interchangeable.

Bottom Line

9004 and 9005 bulbs are fundamentally different. The 9004 is a dual‑filament, combined low/high-beam bulb with a three‑prong base; the 9005 is a single‑filament high‑beam bulb with a two‑prong, right‑angle base. They do not fit the same socket and should not be swapped.

Summary

9004 (HB1) and 9005 (HB3) bulbs are not the same and are not interchangeable. They differ in filament count, connector design, intended use, and optical geometry. Always install the exact bulb type specified for your vehicle to ensure proper beam pattern, safety, and electrical compatibility.

Can I use 9004 instead of 9005?

As a result, they generate distinct beam patterns and are not interchangeable. What is the difference between 9004 and 9005? The 9005 bulb only has a single filament and is meant solely for high beams. While the dual-filament 9004 can serve as both high and low beams, the 9005 can only be used for high beams.

Is a 9004 bulb high and low beam?

Both 9004 bulbs and H4 bulbs are dual function lights that can be used for high beam and low beam. They use similar plug connectors and are also similar in appearance.

What can I use instead of 9005?

The most direct equivalent for a 9005 bulb is the HB3, as they are often used interchangeably. Other equivalent bulbs with the same base include H10, 9011, 9012, 9040, 9045, 9055, 9140, 9145, 9150, and 9155, though there can be minor differences in wattage or light output. 
Direct Equivalents 

• HB3: This is essentially another name for the 9005 bulb and is a perfect, direct equivalent with the same base and applications.

Other Equivalents
These bulbs share a similar base design with the 9005 and can fit the same socket, although there might be slight variations in their design, wattage, or the amount of light they produce. 

• H10
• H12
• 9011
• 9012: (also known as HIR2)
• 9040
• 9045
• 9055
• 9140
• 9145
• 9150
• 9155

What bulbs are interchangeable with 9004?

The primary equivalent for a 9004 bulb is the HB1 (High Beam/Low Beam 1), as they are essentially interchangeable designations for the same automotive halogen bulb type. Always confirm your vehicle’s specific requirements, as other 9000-series bulbs, like the 9007, have different pin configurations and are not interchangeable with the 9004. 
Why HB1 is the Equivalent: 

• Same Function: Both the 9004 and HB1 refer to the same dual-filament, dual-beam headlight bulb used in vehicles.
• Manufacturer Designation: “HB1” is a designation used by some manufacturers and retailers in the United States for the same bulb that the industry standard calls “9004”.

Important Considerations: 

• Do NOT Swap with 9007: While they may look similar and both are dual-filament, a 9004 bulb has a different base type and pin configuration than a 9007 bulb. Attempting to swap them will not work and could damage the electrical system, according to this article from rimthin and sealight.
• Verify Your Vehicle Manual: To be certain, it’s always best to consult your vehicle’s owner’s manual or check the existing bulb’s part number to ensure you purchase the correct replacement, says this article from rimthin.