Scene activated

Use this trigger when you want an automation to run every time a scene is activated. This is useful when activating a scene should also kick off follow-up actions, such as sending a notification, starting media playback, or adjusting devices that are not part of the scene itself.

Using this trigger from the user interface

If you prefer building automations visually, Home Assistant walks you through this trigger step by step. You pick what to watch, tweak a few options, and save. No YAML knowledge required.

To use this trigger in an automation:

1. Go to Settings > Automations & scenes.
2. Open an existing automation, or select Create automation > Create new automation.
3. In the When section, select Add trigger.
4. Select what you want to monitor. Under By target (see Targets), select the area, floor, device, label, or scene entity you want to monitor.
5. From the triggers shown for that target, select Scene activated.
6. Select Save.

Options in the UI

This trigger has no additional options beyond the target.

Using this trigger in YAML

If you work directly in YAML, or you want to know exactly what Home Assistant does under the hood, this section has the technical reference. It lists the field names you use in YAML, their types, and which ones are required. For how an automation is built in YAML, refer to Automations in YAML.

In YAML, put the settings that are specific to this trigger under options. Keep target, if the trigger uses one, and general settings such as id, alias, enabled, and variables at the top level, next to trigger.

When this trigger starts an automation, it passes data about what happened to the automation. You can use this trigger data in the templates of your conditions and actions. To see which data is available, refer to Trigger data in templates.

In YAML, refer to this trigger as scene.activated. A basic example looks like this:

trigger: scene.activated
target:
  entity_id: scene.movie_night

This reacts every time scene.movie_night is activated.

Options in YAML

This trigger has no additional YAML options beyond the target.

Targets of the trigger

This trigger requires a target. The target is the object that Home Assistant will watch. You can select a single entityAn entity represents a sensor, actor, or function in Home Assistant. Entities are used to monitor physical properties or to control other entities. An entity is usually part of a device or a service. [Learn more], a device, an area, a floor, or a label as a target, and Home Assistant will watch every matching scene entity behind that target.

• Entity: one specific scene entity, such as scene.living_room.
• Device: every scene entity that belongs to a device.
• Area: every scene entity in a room or area.
• Floor: every scene entity on a floor.
• Label: every scene entity that shares a label.

You can also select different target types in one trigger. For example, you can add a specific entity and an area as targets in the same trigger to monitor both of them at once.

To learn which entities Home Assistant includes for a device, area, floor, or label, and how it handles several entities, refer to Automation targets.

Trigger variables

When the trigger reacts, the trigger variable identifies the entity that made it react. This is useful when a target contains multiple entities, such as a device, area, floor, or label.

The following trigger-specific variables are available:

• trigger.entity_id: Entity ID of the entity that made the trigger react.
• trigger.from_state: Previous state object of that entity.
• trigger.to_state: New state object of that entity.
• trigger.for: Timedelta object of how long the trigger criteria were met, if applicable.

For example, use {{ trigger.to_state.name }} in an action to include the name of the entity that made the trigger react in a notification.

The trigger variable describes the entity that made the trigger react. It doesn’t contain all the entities of the target.

Good to know

• This trigger reacts every time the scene is activated, including when you activate the same scene several times in a row.
• A scene doesn’t have an on or off state. Its state is the date and time when it was last activated. This trigger reacts when that time changes, including the first activation of a new scene.
• Changes to unavailable or unknown do not count as scene activations.
• If you only need to activate a scene from an automation, use the related Activate scene action instead.

Try it yourself

Ready to test this? Go to Settings > Automations & scenes, create a new automation, and add this trigger. Save the automation, and then make the trigger react. For example, change the state of the targeted entityAn entity represents a sensor, actor, or function in Home Assistant. Entities are used to monitor physical properties or to control other entities. An entity is usually part of a device or a service. [Learn more], turn on a light that the trigger monitors, or change its brightness. To check whether the automation ran, open its traces.

More examples

Real scenarios where this trigger fires in automations and scripts. Copy any example and adapt it to your setup. In the visual editor, select the UI options listed in the example when they are available, or paste the YAML code.

Automation: switch the TV to the movie source when the movie night scene is activated

When you activate the movie night scene, this automation also switches the living room TV to the HDMI 1 input. This is useful when the TV isn’t part of the scene, for example, because other scenes or people use the TV too.

• Trigger: Scene activated
  • Target: Movie night scene
• Action: Select media player source
  • Target: Living room TV
  • Source: HDMI 1

- alias: "Switch TV to movie source on movie night"
  triggers:
    - trigger: scene.activated
      target:
        entity_id: scene.movie_night
  actions:
    - action: media_player.select_source
      target:
        entity_id: media_player.living_room_tv
      data:
        source: "HDMI 1"

Still stuck?

To find out why the trigger didn’t react, make the change that it should react to, and then open the traces of the automation. If the automation didn’t run, there’s usually no trace, but some triggers record a Did not trigger trace. For details, refer to Testing automations. For common problems and their solutions, refer to Troubleshooting automations.

If that doesn’t help, the Home Assistant community is quick to help: join Discord for real-time chat, post on the community forum with the trigger you’re using and what you expected to happen, or share on our subreddit /r/homeassistant.