20 Amp Breakers: What You Need to Know

When you need to run an electrical load, you turn to your breaker box for help. These protective devices have been around since the invention of electricity.

But while they might look like a no-brain device, understanding how they work and how to choose the right breaker for the rated load can make you a better electrician.

In this article, we will study a 20-amp breaker, and the uses.

What is a 20-amp Circuit Breaker?

A 20-amp circuit breaker is a type of breaker that protects our homes from surge.

It is a type of breaker used on sockets and power circuits to protect against overload and short circuits.

This receptacle can withstand a maximum load of 2400 watts before tripping off.

Uses of a 20-amp circuit

The 20 amp receptacle is connected to the power circuits and sockets wired to a 120 volt circuits.

This helps in plugging appliances, laundry, and bathroom circuits.

It is also useful in the kitchen for plugging fridges, but not for high energy consumers like cooker unit, AC, and water heaters that require 30 amp circuit breakers.

Required Wire gauge

A 20-amp circuit breaker requires a 12 gauge wire for optimum performance and maximum protection. Using the wrong gauge of wire can lead to overload or fire hazard.

Number of outlets a 20 ampere circuit can carry

Normally, a single device draws a maximum power of 180 watts (1.5 amp), while a 20-amp circuit carries a maximum load of 2400 watts before tripping.

If you multiply 1.5 amp by 13, you get 19.5 amp. This means you can plug in 13 devices at a time.

But can this give the desired result?

The answer is no. Plugging up to 13 devices into one circuit may not allow even distribution of power among the devices, and some may not get enough power for start up.

Also, loading the circuit up to 90% will cause the breaker to trip. That is why the National Electric Code (NEC) recommends 80% or less load for breakers and circuits

This 80% rule is important because a sudden surge from big appliances may consume the remaining 20% which serves as a free space in the circuit.

Therefore, a 20-amp circuit can comfortably carry a load of 1920 watts or 16 amps on a 120V system.

If you divide 16 amp with 1.5 amp, you get 10.67.

So, a 20 amp breaker can comfortably carry 10 outlets.

Difference between a 15 and 20 amp receptacle

The two breakers are the same and also do the same work. Their difference only lies in the gauge of wire they use.

15 amp uses 14 gauge wires while 20 amp uses 12 gauge wires.

Can I replace a 15A circuit breaker with 20 amp?

Yes, you can upgrade your 15 amp to a 20-amp circuit if you have heavy load appliances.

But before changing the breaker, make sure your wiring has a normal gauge wire, which is a 12 gauge, that can carry that level of current safely.

Once the wire gauge is normal, replacing the breaker will only take a few minutes.

But if the branch circuit is a 14 gauge wire, you will have to replace it with a new 12-gauge wire first before installing a 20-Amp circuit breaker in the electrical panel, and a 20-Amp outlet at the end of the circuit.


The regulations in the NEC are put in place to ensure we use safe practices when using electricity in the home. You should not change the electrical system in your home that contravene any of these regulations since they are there to make the systems safer in the house.