E26 vs E27 Bulb: Mechanical and Electrical Safety Differences

E26 vs E27 Bulb differences

Many believe that there is not much difference between E26 and E27. The initial of both the bulb types being the same doesn’t mean that you can use the two names interchangeably. Two choices are given two names for a reason. Today, we discuss some pointers about the two options available for our readers to have a clear idea.

At the end of our article, you will understand the differences between the two from different perspectives. You will also know if you can use the former bulb in the socket of the latter and vice versa. Make better and informed choices when it comes to lighting your space.

Beware of Untrue Advises


You will often come across several sellers who state that both bulbs are the same. They will also say that you can use their sockets interchangeably. Though the statement is not true, you should not mistake using them interchangeably.

One of the most common statements they use is that “both the bulbs have a difference of one millimeter in diameter. The former is twenty-six mm, and the latter is twenty-seven millimeters, so they are close enough. You will not face any problem even if you put the latter bulb in the former’s socket.”

This information is incorrect, so you shouldn’t follow the advice given. If both the bulb types are manufactured according to the universal standards IEC, then the base of both lamps have almost similar diameters. The specifications are twenty-six mm to twenty-six points five mm.

The two items are extremely different in screw threads and light contact. A key reason for the difference is the voltage range the lights are meant to function. Because of this, the voltages required by both bulbs are different. The first one works with 120V AC and the other works with 240V AC voltage.

On the other hand, don’t forget that light bulbs may be changed manually. One of the lights may be used instead of the other.

Electrical components that aren’t properly connected may result in fires and electrical short circuits, among other issues. It is generally safe to use E27 base bulbs in E26 base light holders. This is because the lamp holder’s voltage is greater than the bulb’s.

On the other hand, most people believe that vice versa is also true. They think using an E26 bulb in a lamp holder that wasn’t designed for an E26 bulb is safe. However, this is not the case.

The Mechanism

Bulb mechanism

Despite having the same diameter, both choices have some mechanical differences as well. We discuss them below for our readers to know better.

The standards of the IEC govern the manufacturing process of the bases of the Edison lamps. The standards lay out the required diameter of both lamps. It means that they already define the size of the base of each lamp so that there is no confusion afterward.

As the name suggests, both options have a difference of one mm in their base, but virtually both are the same. There are some significant differences shared between the two as well.

Considering The Electrical Aspect

Bulb lighting

Mechanical differences between both options are negligible, so we will discuss some of the other points of distinction to help you understand better.

The fact that each light has its voltage and that the lamp bases are constructed in various ways to suit various sockets are two of the most crucial features. The most prevalent design in North America is 26 lights, which 120V AC normally powers.

The second option is for persons living in areas where 240V AC is used in most houses and businesses.

Because the 27 alternate bases were designed for use in high-voltage circuits, users must exercise extreme caution while using them.

As a result, a safe zone might be maintained between the passive and active exchanges. These were some of the E26 v E27 bulbs: Mechanical and Electrical Safety Differences!

Some of the other specific mechanical differences between the two options are listed below;

  • The twenty-seven choice employs a wide thread through diameter to make sure that they offer a more tight and more secure contact. Furthermore, it offers additional protection from debris and dirt since they cannot enter the socket. As far as high voltage levels are considered, the electrical fire risks and short circuits get increased because of contamination and moisture.
  • The twenty-seven Edison bulb employs a long screw since it offers extra precision while aligning the screw to the socket. If the screw of the lamp is not aligned properly, the live point of contact will come close to the neutral screw threads. This helps increase the risk of a short circuit or an electrical arc.
  • The twenty-seven lamp options generally require a tall insulator height so that the distance between the neutral screw base and the live contact is increased to a great extent. Therefore, the difference is significant and necessary to make sure that all sorts of sort circuits and other similar risks can be avoided.

The Bottom Line

bulb for living room

We hope now you are aware of the differences between the two types of bulbs available in the market. Both serve different purposes and hence should not be confused with one another.

Even if the manufacturer says that both lamps are the same and can be easily used interchangeably, be cautious.

Now that you understand some significant and notable differences between the two, you should use the ideal one. You can use the twenty series in the sockets of the twenty-six bulbs but cannot do vice versa since it poses some significant health hazards.

Shoppers of the Edison bulbs are often confused with the two options, so we have helped make a choice easy for them.


How many watts is the E26 bulb?

The E26 variant is commonly available at 100 watts. This is the most bought option by homeowners. This pick imparts a decent amount of light that is sufficient to light a medium-sized room.

How will one know what the base of a light bulb is?

You will have to identify and understand the pattern of the base to know which type it is. See and know if the base is a screw-type and has threads available around the base or if is it a pin-type with 2 points of contact on the base.

To know the exact measurement, you can measure the diameter of the screw base or the distance between the two points in millimeters.If you use these light for photography, you can use Adobe Express photo editor to remove all the light flares