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Complete Smart Home Voice Commands Guide 2026 — Alexa, Google, and Siri

Last Updated: May 21, 2026 | Commands Listed: 80+

The complete reference for smart home voice commands across Alexa, Google Home, and Apple Siri/HomeKit. Bookmark this page — it's the fastest way to find a command you can't remember.

Commands are organised by device type, not by platform, so you can quickly compare how each assistant handles the same request.

Smart Lighting Commands

Action	Alexa	Google Home	Siri (HomeKit)
Turn on lights	"Alexa, turn on [room] lights"	"Hey Google, turn on [room] lights"	"Hey Siri, turn on [room] lights"
Turn off lights	"Alexa, turn off [room] lights"	"Hey Google, turn off [room] lights"	"Hey Siri, turn off [room] lights"
Dim to percentage	"Alexa, set [room] lights to 40%"	"Hey Google, dim [room] lights to 40%"	"Hey Siri, set [room] lights to 40%"
Change colour	"Alexa, change [light] to blue"	"Hey Google, change [light] to blue"	"Hey Siri, change [light] to blue"
Warm/cool white	"Alexa, set [light] to warm white"	"Hey Google, set [light] to warm"	"Hey Siri, make [light] warmer"
Activate a scene	"Alexa, turn on Movie Mode"	"Hey Google, activate Movie Mode"	"Hey Siri, Movie Mode"
All lights off	"Alexa, turn off all the lights"	"Hey Google, turn off all lights"	"Hey Siri, turn off all lights"
Bright light	"Alexa, set [room] to bright"	"Hey Google, brighten [room] lights"	"Hey Siri, full brightness [room]"

Smart Thermostat Commands

Action	Alexa	Google Home	Siri (HomeKit)
Set temperature	"Alexa, set thermostat to 21 degrees"	"Hey Google, set thermostat to 21"	"Hey Siri, set temperature to 21"
Check temperature	"Alexa, what's the thermostat set to?"	"Hey Google, what's the thermostat at?"	"Hey Siri, what's the temperature set to?"
Turn up heating	"Alexa, increase the temperature by 2 degrees"	"Hey Google, turn up the heat 2 degrees"	"Hey Siri, make it warmer"
Turn on heating	"Alexa, turn on the thermostat"	"Hey Google, turn on the heat"	"Hey Siri, turn on heating"
Set to eco mode	"Alexa, set thermostat to eco"	"Hey Google, set thermostat to eco"	Via automation only
What temperature is it?	"Alexa, what's the temperature inside?"	"Hey Google, what's the temperature at home?"	"Hey Siri, what's the temperature?"

Smart Lock Commands

Action	Alexa	Google Home	Siri (HomeKit)
Lock the door	"Alexa, lock the front door"	"Hey Google, lock the front door"	"Hey Siri, lock the front door"
Check lock status	"Alexa, is the front door locked?"	"Hey Google, is the front door locked?"	"Hey Siri, is the front door locked?"
Unlock (with PIN)	"Alexa, unlock the front door" [PIN required]	"Hey Google, unlock the front door"	"Hey Siri, unlock the front door"

For security, Alexa requires a voice PIN for unlock commands. Set this in the Alexa app: Devices → your lock → Lock Settings → Voice Code. This prevents accidental or unauthorised unlocking by voice.

Smart Plug Commands

Action	Alexa	Google Home	Siri (HomeKit)
Turn on plug/device	"Alexa, turn on the [device name]"	"Hey Google, turn on [device name]"	"Hey Siri, turn on [device name]"
Turn off plug	"Alexa, turn off the [device name]"	"Hey Google, turn off [device name]"	"Hey Siri, turn off [device name]"
Check if on	"Alexa, is the [device] on?"	"Hey Google, is [device] on?"	"Hey Siri, is [device] on?"
Schedule on/off	Via Routines in Alexa app	Via Automations in Google Home app	Via Automations in Home app

Security and Camera Commands

Action	Alexa	Google Home	Siri (HomeKit)
Show front door camera	"Alexa, show me the front door" [Echo Show]	"Hey Google, show front door camera" [Nest Hub]	Via Home app only
Arm security system	"Alexa, arm the security system"	"Hey Google, arm security"	"Hey Siri, set home security to away"
Check door status	"Alexa, is the back door open?"	"Hey Google, is the back door open?"	"Hey Siri, is the back door open?"

Routines and Scenes

Action	Alexa	Google Home	Siri (HomeKit)
Goodnight routine	"Alexa, goodnight"	"Hey Google, goodnight"	"Hey Siri, goodnight"
Good morning	"Alexa, good morning"	"Hey Google, good morning"	"Hey Siri, good morning"
I'm home	"Alexa, I'm home"	"Hey Google, I'm home"	Via arrival automation
Leaving home	"Alexa, I'm leaving"	"Hey Google, I'm leaving"	Via departure automation
Movie mode	"Alexa, movie time"	"Hey Google, movie mode"	"Hey Siri, movie time"

Tips for Better Voice Control

Name Your Devices Consistently

The most common voice control problem: inconsistent naming. "Kitchen light", "kitchen ceiling", "big kitchen light" — pick one name per device and use it everywhere. Voice assistants match exact names. "Alexa, turn on the kitchen" works if there's a group called "Kitchen". "Alexa, turn on kitchen ceiling light" only works if that's the exact device name.

Create Groups for Room Control

In Alexa, Google, and HomeKit: create room groups. Add all devices in a room to the group. Then "Alexa, turn off the living room" switches everything off in one command. Set this up once and save hundreds of individual commands.

Use Routines for Common Sequences

Don't say 5 voice commands when one routine does the same thing. "Alexa, goodnight" can: turn off all lights, lock the front door, turn down the thermostat, and arm the security system — all in one phrase. Create routines for your most-repeated sequences.

Rename Devices to Natural Language

Don't name a device "Smart Plug 1". Name it what you'd naturally say: "Coffee machine", "Bedroom fan", "Christmas tree". Voice commands feel natural when the names are natural.

Troubleshooting Voice Commands

Problem	Likely Cause	Fix
"Device not found"	Name mismatch or device offline	Run device discovery or check device is online
"I can't reach that device"	Device offline, WiFi issue	Check device app, power cycle the device
Wrong device responds	Similar device names	Rename devices to be more distinct
Command ignored	Wake word not heard	Speak towards device, reduce background noise
"That's not supported"	Command not available on that platform	Check command table above, use correct syntax

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