110 vs 120 Outlet Voltage Differences

There’s no real difference between 110 and 120V outlets. These are the same outlets with different voltages and are now generally referred to as 120v outlets in the US.

It used to be the case that 110 outlets were called 110 outlets. Today, even 110 outlets are called 120V outlets as these are the norm for home outlets.

110 vs 120 outlets – is there a difference?

An acceptable voltage difference at the outlet is within the 5% range. This means a 120V outlet doesn’t necessarily need to run on 120V. It can run on 110V, 115V, 117V.

Voltages aren’t really important today as there are minimum voltage appliances that need to work with. You can calculate the minimum voltage of a certain appliance. However, this minimum voltage is often printed on its packaging.

So why is there still a difference between 110V and 120V in measured power at the outlet?


The physical distance the outlet is located at from the main power line on the street is one of the factors that influence constant voltage or voltage ranges.

120V is the standard outlet according to electricians. But this is not always 120V and distance might be affecting the final results (not in an unsafe way in most cases)


Wires are also important. High-duty wires are the best for true 120V. Low-quality wiring is almost always limiting the power of output of an outlet.

Corrosion stage

Even good wires can impact voltage at the outlet. High levels of corrosion and sometimes even low levels of corrosion can trigger voltage variation within the 5% range.

Some electricians from other countries know the acceptable range difference in power output can be even higher. It’s common for this difference to be 6-10% outside the US.


All connectors have an important role in the output of a 120V outlet.

A maximum of 5% load differences

5% load differences are tolerable, acceptable, and common. These are encountered in almost every home, especially if there’s an older electrical circuit within the home.


Are outlets 110 or 120V?

110V outlets are old terms used to describe approximate power. 120V outlet terms are more common today. Both 110 and 120V now describe the same outlet.

Is home voltage 110 or 120V?

120V is the standard nominal voltage in US homes. It’s sometimes referred to as 110V, 115, or 117V. Outlets in US homes are 120V. They power all types of appliances as electricals such as refrigerators, microwaves, dryers, and treadmills.