What you need
A smart plug for a lamp, or a smart bulb in a fixture. The Kasa KP125M and WiZ Full Color both work with every major app through Matter. Make sure your home app knows your location, since that’s how it knows when sunset is.
Apps rename their menus from time to time, so the exact labels below may differ slightly on your phone. The steps stay the same.
Plug, bulb or switch?
Pick by the light you want to automate:
- Table and floor lamps: a smart plug. You keep the bulb you like, and one plug runs the whole lamp.
- Ceiling fixtures, and lamps you want to dim or change color: a smart bulb. Leave the wall switch on, because a bulb with no power can’t hear the routine. WiZ also advises against putting its bulbs on a dimmer switch.
- Fixtures with several bulbs on one switch: a smart light switch handles them all at once, but it’s a wiring job, so it’s for owners rather than renters.
- Porch and string lights: an outdoor plug rated for the weather. See the best outdoor smart plugs.
In the Alexa app
Alexa calls these routines.
- 1Open the Alexa app and tap More, then Routines, then the plus sign.
- 2Choose ‘When this happens’, then Schedule, then Sunset.
- 3Add an action: Smart Home, pick your lamp, set it to On.
- 4Save. Repeat with a fixed time, like 11 pm, set to Off.
In Google Home
Google calls these automations.
- 1Open Google Home and go to Automations, then Add.
- 2Pick Household, then add a starter: Sunrise/sunset, then Sunset.
- 3Add an action: Adjust home devices, pick your lamp, turn On.
- 4Save, then create a second automation to turn it off at bedtime.
In Apple Home
Apple calls these automations, and they need a home hub (HomePod or Apple TV).
- 1Open Home, tap the plus sign, then Add Automation.
- 2Choose ‘A Time of Day Occurs’, then Sunset.
- 3Choose your lamp and set it to turn on.
- 4Tap Done, and add another automation to turn it off.
No smart speaker? Use the maker’s app
You don’t need Alexa, Google Home or Apple Home for this. The Kasa app, which runs the KP125M, can schedule a plug to turn on at sunset and off at sunrise or a set time (TP-Link). The WiZ app has its own schedules too, including sunset-to-sunrise lighting (WiZ). Kasa’s Away Mode is handy while you travel: it switches lights on and off at varying times so the house looks lived-in.
Schedule each light in one place only. If the Kasa app and an Alexa routine both control the same lamp at different times, they can undo each other, and the lamp seems to have a mind of its own.
Make it smarter
A few easy upgrades:
- Add an offset, like 15 minutes before sunset, for darker rooms, if your app offers one.
- Only run it when someone is home, using the app’s presence option.
- Use warm white after dark if your bulbs support color temperature.
- For hallways and bathrooms, a motion sensor such as the Aqara P2 turns lights on only when someone walks in.
If the light doesn’t come on
Most failures come down to one of these:
- It came on at the wrong time. Sunset is worked out from the location your app has. In Alexa, check your Echo’s device location, especially after a move. In Google Home, check the home address in the app’s settings.
- Nothing happened. Try the light from the app. If it shows as offline, it has dropped off Wi-Fi; our 2.4 GHz guide covers devices that keep dropping off.
- A smart bulb didn’t respond. Check the wall switch: if someone turned it off, the bulb had no power.
- Apple Home skipped it. Automations run on your HomePod or Apple TV, so check that it’s on and connected under Home Hubs & Bridges in the Home app’s settings.
- It turned on, then off again. Another schedule is fighting it, often one set up earlier in the maker’s app. Delete one of them.
Where these facts come from
We haven’t walked through these apps ourselves. The steps follow Apple’s, Google’s, TP-Link’s and WiZ’s help pages and How-To Geek’s Alexa guide, checked on September 30, 2026. Apps change their menus often, so tell us through the contact page if a step has moved:
