Button

A button 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] is an entity that can fire an eventEvery time something happens in Home Assistant, an event is fired. There are different types of events, such as state change events, when an action was triggered, or the time changed. All entities produce state change events. Every time a state changes, a state change event is produced. Events can be used to trigger automations or scripts. For example, you can trigger an automation when a light is turned on, then a speaker turns on in that room. Events can also be used to trigger actions in the frontend. For example, you can trigger an action when a button is pressed. [Learn more] or trigger an actionActions are used in several places in Home Assistant. As part of a script or automation, actions define what is going to happen once a trigger is activated. In scripts, an action is called sequence. [Learn more] toward a deviceA device is a model representing a physical or logical unit that contains entities. or serviceThe term “service” in Home Assistant is used in the sense of an information service. For example, the municipal waste management service that provides entities for organic, paper, and packaging waste. In terms of functionality, the information service is like a device. It is called service to avoid confusion, as it does not come with a piece of hardware., but remains stateless from the Home Assistant perspective.

It can be compared to a momentary switch, push-button, or other form of stateless switch.

The state of a button

The button 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] is stateless. Unlike a normal switch entity, it does not have an on or off state.

The state of a button is a timestamp showing when the button was last pressed via the Home Assistant UI or an action.

Screenshot showing the state of a button entity in the developer tools.

In addition, the entity can have the following states:

• Unavailable: The entity is currently unavailable.
• Unknown: The state is not yet known.

You can use button entities in automations to react when a button is pressed, or to simulate pressing the button from Home Assistant, like pressing a physical button on the device itself.

List of triggers

The Button integrationIntegrations connect and integrate Home Assistant with your devices, services, and more. [Learn more] provides the following triggers. Each link below opens a dedicated page with examples, fields, and a step-by-step UI walkthrough.

• Button pressed (button.pressed) Runs when a button entity is pressed.

For an overview of every trigger across all integrations, see the triggers reference.

List of actions

The Button integrationIntegrations connect and integrate Home Assistant with your devices, services, and more. [Learn more] provides the following actions. Each link below opens a dedicated page with examples, parameters, and a step-by-step UI walkthrough.

• Press button (button.press) Presses a button entity.

For an overview of every action across all integrations, see the actions reference.

Device class

A device class is a measurement categorization in Home Assistant. It influences how the entity is represented in the dashboard. This can be modified in the customize section. For example, different states may be represented by different icons, colors, or text.

The screenshot shows different icons representing different device classes for buttons:

Example of device class icons.

The following device classes are supported for buttons:

• None: Generic button. This is the default and doesn’t need to be set.
• identify: The button is used to identify a device.
• restart: The button restarts the device.
• update: The button updates the software of the device.

Button automation examples

The following examples show how you can use button entities in automations.

Automation: send a notification when a button is pressed

Use the button trigger to react when you press a button entity, like a reset or maintenance button.

• Trigger: Button pressed
  • Target: Air purifier filter reset button
• Action: Send a notification message
  • Target: My Device (notify.my_device)

- alias: "Notify when the filter reset button is pressed"
  triggers:
    - trigger: button.pressed
      target:
        entity_id: button.air_purifier_reset_filter
  actions:
    - action: notify.send_message
      target:
        entity_id: notify.my_device
      data:
        message: "The air purifier filter reset button was pressed."

Automation: restart a device with a button action

Use the button action when an integration exposes a restart or update button that you want to run from an automation.

• Trigger: Internet connection turns off for 10 minutes
• Action: Press button
  • Target: Router restart button

- alias: "Restart the router when the internet has been down"
  triggers:
    - trigger: state
      entity_id: binary_sensor.internet_connection
      to: "off"
      for: "00:10:00"
  actions:
    - action: button.press
      target:
        entity_id: button.router_restart