Are A15 and A19 Bulbs Interchangeable ?

Are A15 and A19 Bulbs Interchangeable ?

To light your home or office, it's important to know the different types of light bulbs you can buy. Two common types are A15 and A19 bulbs. Both serve similar purposes but have distinct differences that can impact their interchangeability. In this blog, we'll explore whether these two bulbs are interchangeable.


Before moving on to the answer “Are A15 and A19 bulbs interchangeable”, let us understand the basics. That would be very helpful for you. 

What are A15 Bulbs?

A15 bulbs are a kind of light bulb that can be incandescent or LED. They are part of the "A" series and have a pear-shaped design. 

  • People commonly use these smaller bulbs, around 1.875 inches wide, in small fixtures such as desk lamps and ceiling fans.
  • A15 bulbs have a reputation for emitting focused and directional light, which makes them perfect for task lighting.

What are A19 Bulbs?

A19 LED bulbs are bigger than A15 bulbs, even though they are both part of the "A" series. 

  • They have a diameter of approximately 2.375 inches and people often use them in larger fixtures, pendant lights, and ceiling fixtures.
  • A19 bulbs provide a broader and more diffused light, suitable for general illumination.

Differences Between A15 and A19 Bulbs

Now let's compare and find the differences between these two lighting fixtures after understanding their basic features. 


A15 Bulbs

A19 Bulbs


Smaller: Approx. 1.875 inches in diameter

Larger: Approx. 2.375 inches in diameter

Ideal Use

Task lighting in smaller fixtures, like desk lamps and ceiling fans

General illumination in larger fixtures, such as pendant lights and ceiling fixtures

Light Emission

Focused, directional light

Broader and more diffused light

Fixture Compatibility

Suitable for smaller fixtures

Suitable for larger fixtures

Wattage and Lumen Output

Typically lower wattage and lumens

Potentially higher wattage and lumens, which can affect energy consumption

When Can You Interchange Them?

In our process of getting the answer to “Are A15 and A19 bulbs interchangeable”, let us explore another aspect. A15 and A19 bulbs can interchange in some cases, but they must meet certain conditions. Here's when you can consider swapping them:

Fixture Compatibility

Both A15 and A19 bulbs have a standard medium E26 base, which is the most common base type. If your fixture can accommodate this base, you can generally interchange A15 and A19 bulbs without any issues.

Wattage and Lumens

Before making the switch, ensure that the A19 bulb's wattage and lumen output are suitable for the fixture. A19 bulbs may have higher wattage or lumen output, which can affect the lighting quality. Check the fixture's specifications to make sure the interchange won't overload it or create too much light.

In most cases, A15 and A19 bulbs can be interchangeable.  However, the size and light quality differences should be considered.

How to Replace A15 with A19 Bulbs

If you decide to replace an A15 bulb with an A19 bulb, follow these steps:

Step-by-Step Guide

  • Turn off the power to the fixture by switching off the circuit breaker or unplugging it.
  • Remove the A15 bulb from the fixture by unscrewing it counterclockwise.
  • Screw in the A19 bulb clockwise until it's snug but not overly tight.
  • Restore power to the fixture and check the lighting to ensure the A19 bulb works properly.


Getting the answer to “Are A15 and A19 bulbs interchangeable” can be helpful in increasing the ambiance of any space. A15 and A19 bulbs can be interchangeable in some situations, mainly when they have the same base and wattage. However, you must be mindful of the differences in size and light quality to ensure you meet your lighting needs.


Got a question? Here, you will find frequently asked questions and their answers. 

  • Can I replace my A15 bulb with an A19 bulb?

  • Yes, you can replace an A15 bulb with an A19 bulb if the fixture can accommodate the larger bulb and if the wattage and lumens are compatible.

  • Do A15 and A19 bulbs have the same base?

  • Both A15 and A19 bulbs have a standard medium E26 base, making them compatible with the base.

  • Will using A19 bulbs affect energy consumption?

  • A19 bulbs may have higher wattage and lumen output, which can result in higher energy consumption. Check the fixture's specifications to ensure it can handle the increased load.

  • Are there any advantages to using A15 bulbs over A19?

  • A15 bulbs are smaller and provide focused, directional light, making them ideal for task lighting in smaller fixtures.

  • Are there any disadvantages to using A19 bulbs in place of A15?

  • A19 bulbs are larger and provide more diffused light, which may not be suitable for all fixtures. Additionally, they may consume more energy. Consider the lighting requirements of your specific fixture before making the switch.