What is a Smart Light Switch?

Use your voice to turn on the lights, ceiling fan, or even the fireplace

Smart light switch with smartphone app control.
 Getty Images

A smart light switch is a network-enabled smart home device that allows you to control hardwired lights, ceiling fans, and even fireplaces with an app from your smartphone or with you voice using a virtual assistant. Smart switches add smart home features to anything you turn on or off with the flip of a switch.

What Can a Smart Light Switch Do?

A smart light switch or smart switch lets you control anything in your home connected to a switch with your voice or a smartphone app. Use smart switches to control lights, ceiling fans, bathroom fans, switch-controlled fireplaces, and even the garbage disposal.

Let's look at some of the features you might expect to find in a smart switch:

  • Wi-Fi connectivity integrates your smart switches into your connected smart home.
  • Turn switches on and off using the voice control capabilities from Google Assistant or Amazon’s Alexa. If your smart home is set up with Apple HomeKit, make sure to select smart switches specifically labeled as compatible with HomeKit — switches without this feature indicated aren’t compatible with HomeKit and Siri.
  • If your smart home system uses a hub such as Wink 2 or Samsung SmartThings, double-check for compatibility with Z-Wave or ZigBee, depending on the technology standard used by your smart hub.
  • Use your smartphone to create custom schedules to turn switches on and off at specific times or turn switches on or off manually with your smartphone while away from home
  • Select smart dimmer switches for more precise control of lighting in the kitchen, dining room, bedroom, and living room.

Note: Specific features vary by brand and model. This overview covers the range of features and options available from multiple smart switch manufacturers.

Common Concerns About Smart Light Switches

Some smart switches need to be installed in place of your traditional switches, which involves some knowledge and working with electrical wiring. Let’s review installation and other smart light switch concerns many consumers have.

What is required to install and use smart switches?

Smart light switches require an available neutral wire or neutral line to work. Current building codes require a neutral line throughout the home for all switches and outlets, however, if your home was built prior to 1990, it is possible you might have switches without a neutral line. Even in older homes, switches located close to an outlet and switch units with multiple switches often do have a neutral line. To determine if your wiring is appropriate for a smart switch, you can check fairly easily.

  1. First, for safety, always turn off electricity to the room or to the entire home at the breaker before doing anything electricity-related in your home — even just looking at wiring.
  2. Remove the switch cover for the switch(es) where you’d like to install smart switches and examine the wiring. In the United States, home wiring consists of either three or four plastic-coated cables gathered into a larger plastic-coated wiring line.
  3. The individual cables from within the wire can be identified by the color of their plastic covering (or lack of covering for the ground wire). ​
    • The black cable is the hot line that brings power to the switch (if a red cable is present, that is also a hot line).
    • The bare copper wire is the ground wire that grounds to the earth for safety.
    • The white cable is the neutral line and is the one you need to see in the switch wiring to be able to install a smart switch.

What if there is no neutral line for the switch I want to replace with a smart light switch?

If you don’t see a white plastic-covered cable within the larger wiring line, your home’s wiring might not be compatible with smart switches without having the wiring updated to current building codes. A qualified electrician can examine your wiring and provide more information on any necessary upgrades.

There are also some smart switches that install on top of the existing light switch. These devices are battery powered and use magnets to snap into place over the existing switch without the need to mess with the wiring. However, they can be less reliable than hard wired switches and they may not integrate with your smart home hub or virtual assistant. We suggest you review these devices carefully before sinking your home automation dollars into something that might not suit your needs.

How much does a smart switch cost?

Wi-Fi compatible smart light switches range from $25 to around $100 depending on the features included. If the smart switch requires a bridge or other equipment to work with your connected smart home network or hub, that equipment will add to the overall cost.