6 Crucial Reasons Why a Smart Switch Needs a Neutral Wire


why does a smart switch need a neutral wire

When it comes to home automation, one of the most seamless ways to upgrade your lighting is with a smart switch.

Using a smart switch allows you to control your lights from the wall with the added benefits of dimming and remote control. But why is it really that it needs a neutral wire?

A smart switch requires a neutral wire connected to it to gain energy from a power source and deliver all the automation capabilities that it was designed for. Without one, it is going to act as a regular switch and you won’t be able to operate it remotely

Most homes built after 1985 will have a neutral wire in the junction box, but there are many older homes that do not.

Though there are a few models on the market that don’t require a neutral wire, it is still a good idea to have a neutral wire in your home to keep your smart switches working optimally.

Besides that the fact that is not going to work as a smart switch, keep reading for six more reasons why is it is necessary to have a neutral wire when using a smart switch.  

Without a Neutral Wire, Your Smart Switch Options are Limited

There are far more options available for smart switches that use neutral wire than those that don’t.

When it comes to automating the lighting in your home, you can pretty much use any smart switch on the market if you have a neutral wire in your home. 

Without the neutral wire, your options are much more limited, and they limit even more depending on the smart home platform you’re using.

Amazon Alexa and Google Home tend to have more compatible smart switch options available than Apple Home Kit. 

One option available that doesn’t require a neutral wire and works with Alexa, Home Kit, and Google is the Lutron Caseta Smart Home Dimmer Switch

Equipment Can Become More Expensive

The majority of smart switches that don’t require a neutral wire do require a switching hub or smart home hub in order to communicate with the light switch.

You may also need a bypass resistor or low power adapter for the lights to work properly.  

The smart switches themselves can also run on the higher end when it comes to cost. The Lutron Casesta mentioned earlier costs $59.99 compared to the Meross Smart Light Switch at $20.99. 

Neutral Wire Protects Your LEDs from Damage

For a smart switch to work, it needs to have consistent access to power.

As the hot wire feeds power to the switch, having a neutral wire in your junction box allows the current to return to your electrical panel. 

Without a neutral wire, the current runs through the switch wire, through the light bulb, into the wire in the ceiling, and then back to the electrical panel.

Having a low power current running through the bulb can cause damage over time, lowing the life expectancy of your LED lights. 

You Can’t Connect Your Smart Switch Directly to WIFI Without a Neutral Wire

As mentioned earlier, smart switches that don’t require neutral wire need a hub to operate.

Many of these hubs operate on a proprietary RF frequency, and the hub converts those singles into WIFI commands that can then be controlled from your phone. 

Z-Wave is another technology used in smart switches without a neutral wire.

Z-Wave is a repeating network, so each device broadcasts and communicates with other Z-Wave devices on your network through the hub. 

Without a neutral wire, you need to make sure that not only your router is working but that the required hub for your smart switch is working as well.

With a WIFI smart switch, a separate hub isn’t needed, which means your switches always of direct WIFI access. 

You May Not Be Able to Use LED Bulbs

Just like there is a limit on the smart switches available, there is a limit to the types of bulbs you can use as well. Some of the switches the don’t require neutral wire also won’t work with LEDs or need a bypass resistor to use an LED bulb.

If you’re someone who prefers LED bulbs over incandescent bulbs, not having neutral wire might show to be a problem. 

Protects Your Switch from Faulty Currents

In the United States, most homes use an Alternating Current electrical system, meaning that the electricity travels back and forth.

As the hot wire brings the current in, it starts the circuit.

An insulated white wire called the neutral wire carries that current back to a ground wire in your electrical panel.

This completes the circuit, meaning if anything happened to this wire, the circuit would stop working.

This also prevents faulty or excess currents from residing in your switch. 

Neutral Wire Smart Switches Can Help You Save Energy

Light switch automation and scheduling allow you to set up schedules for your lights at certain times and even access your system when you are away.

You can also lower the lights at certain times of day, helping you cut energy waste and save money. 

Having a smart switch that operates with a neutral wire also allows you to use LED bulbs with your system, saving your additional energy costs. 

How To Check a Switch Box for Neutral Wire

Before buying a smart switch, it is a good idea to check whether or not your box has a neutral wire.

This way, you will know what to look for as you are shopping, so you don’t buy something that won’t work with your setup. 

An easy way to check for neutral wire is to look at the switch box wiring. Here’s what you need to know:

  • First, turn off the main electrical feed of the switch you will be working on and test your voltage with a voltage tester before getting started. 
  • Remove the faceplate of the switch. 
  • Remove the switch from the junction box and check for wires at the back.
  • Look for a white wire among the wires in the switch box. If you find one, then the switch has a neutral wire. If there isn’t a white wire, then that switch doesn’t have a neutral wire.  

How to Install a Smart Switch If You Don’t Have Neutral Wire

If you don’t have a neutral wire, that doesn’t mean you can’t install a smart switch in that location; you’ll just have a few more steps to go through. You have several options to choose from when installing a smart switch in a home that doesn’t have a neutral wire.  

Some will opt for a smart switch that doesn’t require a neutral wire, but as we’ve pointed out, this can be pricy, and your product options are limited.

Also, using a smart switch that doesn’t require neutral wire is more of a temporary fix than a long-term solution, and meaning you may have to upgrade your system at a later date.

Your other option is to add a neutral wire by either extending an existing wire from a different switch box in the house or adding a new neutral wire to the switch.

A professional electrician is required in order to perform either one of these services, as these jobs can be extensive and require knowledge of the entire electrical system in your house. 

why does a smart switch need a neutral wire?Final Thoughts

Smart switches provide a higher level of comfort and convenience than traditional light switches and enhance your home automation experience.

Most of the smart switches on the market require a neutral wire for installation, so they can provide consistent power to the switch using complete a circuit. 

Having neutral wire installed may seem like a strenuous task for homeowners, but once it is wired into your home, you can fully utilize the energy in your house and trust that all your smart home devices are connected and working optimally.

Choosing to connect your smart switch using neutral wire is a lasting energy-efficient enhancement to your home instead of a temporary alternative. 

Nelson Barbosa

I'm an engineer in love with smart home tech. On my website, I share useful tips and tricks to help my readers get the most of their devices and make their lives simpler by adding just a drop of technology in everyday routines!

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