Can You Mix 12/2 and 14/2 Wire

Can You Mix 12/2 and 14/2 Wire? – Answered With 5 Essential Features!


A complete house rewiring process is lengthy and tiring. You may get frustrated determining the right wiring products that suit your house. 

The usage of different kinds of wires in different rooms is a good idea. You can develop an efficient system.

However, can you mix 12/2 and 14/2 wire?

The general suggestion is not to do it because of a few factors. Features such as circuit breaker suitability, conductive capacity, and protection from overheating are highlighted. In addition, the structure and longevity areas cannot be overlooked as well. Both 12/2 and 14/2 have good attributes. 

The deeper you go into researching the topic, the more you will know. We ask you to invest some time reading this article before taking any action. 

Let us begin!

5 Features to Differentiate 12/2 and 14/2 Wires

A common expert opinion is not to mix 12/2 and 14/2 wires. You can physically do it, but it is not recommended for varieties of reasons. 

Getting a new wiring system done in your home means you need to consider some options. The risks that can come about due to mixing the wiring can be many.

Let us see what the chart below indicates. 

WireAmp120V Circuits240V Circuits
14/215 Amp50 Feet100 Feet
12/220 Amp60 Feet120 Feet
10/230 Amp64 Feet128 Feet
8/1240 Amp76 Feet152 Feet

You can be asking can I mix 12 and 14 gauge wire on a 20 amp circuit? The simple answer is no. The chart above showcases the recommended wiring for different amps and voltage. 

We will further discuss five reasons why mixing wires is not a good idea. 

Feature 1: The Breaker Situation

It is important to note that different amperage systems require different kinds of wiring. This is because of how the wires are manufactured with their current flowing ability. 

So if we ask can you use 14-2 wires on a 20 amp breaker? You should be telling us that it is not possible. 

The 12/2 wire is perfectly suitable with a 20 amp breaker. While as the chart suggests, the 14/2 wire would fit the 15 amp breaker. 

When you are installing new circuit breakers around the house, a few issues may arise. This is due to the electrical setup of the house, the wrong circuit breaker won’t fit

The old system of the house has a 20 amp circuit. You may want to install a 15 amp breaker, it won’t work. 

Different areas and rooms around the house may need a different voltage of electricity. This is mainly to ensure energy and cost efficiency.  

The usual question is, why would I need different types of wires for circuit installments?

Although the chart indicates 30 and 40 amperage scenarios, you won’t need that. The lower gauges are good for commercial or broader spaces. For home conditions, the 12/2 and 14/2 are more efficient. For smaller rooms, 14/2 wires are the best while in larger rooms, 12/2 wires are good. 

It is best to do the mixes in this method involving separate rooms. Mixing in the same room is not recommended, simply due to the amp circuit setup. 

Feature 2: Conductive Capacity

The lower the wire gauge numbers get, the more versatile they become. You can ask if can you use 12/2 wire on a 15 amp circuit? The answer is yes, you can do it.

The 14/2 is suitable for a 15 amp circuit. But it cannot work with a 20 amp circuit where 12/2 can suit both the amperages. 

Simply put, you may have a combination of 15 and 20 amp circuits at home. Getting up to 60 feet to 120 feet, 12/2 wires would benefit you. This will provide you with the best cost and energy efficiency. 

Due to different amperage levels, the voltage levels may change. This would normally vary from 120 to 240 volts from room to room. 

The 20 amp circuits are usually recommended as they go well with many powerful appliances. Many houses install 20 amp circuits to suit air-conditioning and heavy heaters. 

Feature 3: Protection From Overheating

The circuit breakers along with the fuses have varied functionalities. One of them is to protect the wiring system from overheating. 

But on most occasions, they default. This is due to an imbalance in the electricity distribution within the wires. This happens when you try to mix the 12/2 and 14/2 wires. 

If you can get a good twist on the wires, you can do something. What you can do is pigtail 12 gauge to 14 gauge. This can work as long as you have the 15 amp circuit breaker. 

However, with a 20 amp circuit breaker, the mixed wires may start to overheat. Things may get dangerous as time passes. 

The different sockets around the house may start to burst. Things can get serious when there are many powerful appliances in the house. 

In addition, several appliances around the room may melt. It can also expose some line polarity issues within the system.

This is not good since you have to spend extra on repair or replacements. 

You can safely put 12 gauge wire on a 20 amp circuit. This will power up the entire house with balanced electricity distribution. 

Feature 4: Structure

In the United States, the government is always there for your safety. The code of conduct states how you should set up the electrical system. 

For example, it is mandatory that you install 20 amp circuits in bathrooms and kitchens. 

So, how far can you run 14 gauge wire on a 15 amp circuit? The recommendation is you cannot go further than 40 feet. This means you have to install a 120V circuit. 

This is not a realistic scenario since a 15 amp circuit is safe with 240 volts. This easily suggests how 14/2 wires are not supported with 20 amp. 

It is good to just install the 14/2 wires in the kitchens and bathrooms. The 120 volts are enough in this area with 15 amperage levels. 

As better absorbers of high voltage levels, 12/2 does well in broader areas. The structure of the 12/2 wires can easily absorb 240 voltage power. 

Feature 5: Longevity

In this entire article we have recommended the 12/2 wires in a more versatile platform. This is because the 12/2 appears as being able to absorb more voltage power. 

However, there are some disadvantages of 12/2 because of its thinner build. Problems such as wear and tear are common with 12/2.

This is why you should not mix the 12/2 and 14/2. A mixture of thinner and thicker wires will just create a bad electric distribution. The thicker 14/2 has some advantages over 12/2. 

The thicker maximum amps for 14 gauge wire is only 15 amperages. This is because the layered 14/2 wires can withstand hot conditions. They are good for outdoor installations where you won’t need more than 15 amperages. 

Being able to resist moisture and heat better, the 14/2 wires last longer. 

Important Points to Notice

In this article we have recommended mixing or not mixing depending on different scenarios. This means you are not allowed to mix the wires in the same room.

But in the entire house scenario, you are allowed to mix, this means externally. This is as long as they are kept separately depending on the circuit breakers. 

Can you mix 12/2 and 14/2 wire? You must check the 15 amp and 20 amp scenarios here. 

There is another situation here that depends on the brand. It is important to ask can you mix yellow and white Romex? When you buy wires of different sizes, they come in terms of white and yellow colors. 

The white Romex is 14/2 and the yellow Romex is 12/2. Since they are of the same brand, many suggest you can mix them. 

You can do it probably in the same circuit, especially in the 15 amperage level. However, for your safety and durability, it is good not to mix them together. 

Southwire 28828221 RomexUsed for residential electrical wiring
Southwire 28827422 RomexLong-lasting cables to be used in 15 amp circuit breaker
Q115 – 15 Amp Circuit BreakerSingle Pole Circuit Breaker
Q120 20 Amp Circuit Breaker120V Capacity Circuit Breaker


Why does lower amperage have high voltage capacity?

Lower amperage is good for high voltage in order to reduce conductor resistance. A higher current with high amperage will flare up the electricity transmission. This can cause damage to the wiring system. 

Which one of the two wires is good for pigtailing?

It is generally recommended to use 12/2 wires for pigtailing. This is because of the thinner layers of the cables. They are able to withstand a higher voltage of energy. 

Can I use 10/2 and 8/2 wires in the 15 amp circuit?

Yes, you can use 10/2 and 8/2 wires in the 15 amp circuit. However, you won’t be able to use 12/2 and 14/2 wires in the 30 and 40 amp circuits. 


We ask again, can you mix 12/2 and 14/2 wire? Hope this article has given a clear idea of wires and circuits compatibility. 

By wishing you all the best, we are singing off.

Bye for now!

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