Why do my lights turn on or off by themselves?

Lights Turning On or Off by Themselves?

The short answer

Lights that switch on or off by themselves are usually following instructions you've forgotten: a smart switch schedule, a routine in an app, a motion or daylight sensor, or a timer. Remote-controlled fittings can also pick up stray signals. If you've ruled those out, or the light flickers, buzzes or goes off when warm, a loose connection or failing driver is the likely cause.

Check the settings first

Smart switches and smart globes often carry schedules, holiday modes, sunset routines or location triggers that switch lights as someone's phone leaves or arrives. These can sit in more than one app, and anyone in the household with access can add one. Voice assistants occasionally mishear a command too. If the light changes at a similar time each day, a schedule is the likely culprit.

Some smart switches go back to on, or to their last state, after a power blip, so lights can appear on in the middle of the night after a short outage. Plug-in timers, timers in the switchboard and hallway motion sensors are easy to forget, especially in a house you've just moved into.

Remotes, sensors and glowing LEDs

Ceiling fans and lights with radio remotes can respond to another remote on the same code, sometimes a neighbour's. Pairing the remote to the receiver again often sorts it. Sensor lights react to pets, swaying plants and passing cars, which looks random from inside.

A faint glow or slow flash from an LED that is switched off is called ghosting. It happens when a small current still reaches the light, often through a smart switch with no neutral or an illuminated switch. It isn't the light turning on, but it can mean the switch and fitting aren't well matched.

When it's a wiring fault

A light that goes off and comes back on its own, especially with flicker, buzzing or a warm switch, may have a loose connection. An LED fitting that switches off when it gets hot and returns after cooling has a driver or heat problem. Both need testing by a licensed electrician, because loose connections and overheating drivers get worse with time.

What you can safely do now

Open every app linked to the lights and check schedules, routines, holiday modes and shared users.
Write down the times it happens. A pattern points to a schedule; random timing points to a sensor, remote or fault.
Look for plug-in timers, and check the switchboard for a timer device.
If a switch is warm, buzzing or crackling, turn the light off and leave it off until it's checked.

Services that can help

Dimmers & Smart Lighting SwitchesDimmers, timers and app-controlled switches and scenes.Sensor LightsMotion and dusk-to-dawn lights for paths, doors and drives.Electrical Repairs & Fault FindingFinding out why circuits trip, flicker or go dead, then fixing them.