Automation Trigger


Triggers are what starts the processing of an automation rule. It is possible to specify multiple triggers for the same rule. Once a trigger starts, Home Assistant will validate the conditions, if any, and call the action.

Event trigger

Triggers when an event is being processed. Events are the raw building blocks of Home Assistant. You can match events on just the event name or also require specific event data to be present.

Events can be fired by components or via the API. There is no limitation to the types. A list of built-in events can be found here.

automation:
  trigger:
    platform: event
    event_type: MY_CUSTOM_EVENT
    # optional
    event_data:
      mood: happy

Starting 0.42, it is no longer possible to listen for event homeassistant_start. Use the ‘homeassistant’ platform below instead.

Home Assistant trigger

Use this platform to trigger when Home Assistant starts up and shuts down.

automation:
  trigger:
    platform: homeassistant
    # Event can also be 'shutdown'
    event: start

MQTT trigger

Triggers when a specific message is received on given topic. Optionally can match on the payload being sent over the topic.

automation:
  trigger:
    platform: mqtt
    topic: living_room/switch/ac
    # Optional
    payload: 'on'

Numeric state trigger

On state change of a specified entity, attempts to parse the state as a number and triggers once if value is changing from above to below a threshold, or from below to above the given threshold.

automation:
  trigger:
    platform: numeric_state
    entity_id: sensor.temperature
    # Optional
    value_template: '{{ state.attributes.battery }}'
    # At least one of the following required
    above: 17
    below: 25

    # If given, will trigger when condition has been for X time.
    for:
      hours: 1
      minutes: 10
      seconds: 5

Listing above and below together means the numeric_state has to be between the two values. In the example above, a numeric_state that is 17.1-24.9 would fire this trigger.

State trigger

Triggers when the state of tracked entities change. If only entity_id given will match all state changes, even if only state attributes change.

automation:
  trigger:
    platform: state
    entity_id: device_tracker.paulus, device_tracker.anne_therese
    # Optional
    from: 'not_home'
    # Optional
    to: 'home'

    # If given, will trigger when state has been the to state for X time.
    for:
      hours: 1
      minutes: 10
      seconds: 5

Use quotes around your values for from and to to avoid the YAML parser interpreting values as booleans.

Sun trigger

Trigger when the sun is setting or rising. An optional time offset can be given to have it trigger for example 45 minutes before sunset, when dusk is setting in.

automation:
  trigger:
    platform: sun
    # Possible values: sunset, sunrise
    event: sunset
    # Optional time offset. This example is 45 minutes.
    offset: '-00:45:00'

Sometimes you may want more granular control over an automation based on the elevation of the sun. This can be used to layer automations to occur as the sun lowers on the horizon or even after it is below the horizon. This is also useful when the “sunset” event is not dark enough outside and you would like the automation to run later at a precise solar angle instead of the time offset such as turning on exterior lighting.

automation:
  alias: "Exterior Lighting on when dark outside"
  trigger:
    platform: numeric_state
    entity_id: sun.sun
    value_template: "{{ state.attributes.elevation }}"
    # Can be a positive or negative number
    below: -4.0
  action:
    service: switch.turn_on
    entity_id: switch.exterior_lighting

The US Naval Observatory has a tool that will help you estimate what the solar angle will be at any specific time.

Template trigger

Template triggers work by evaluating a template on each state change. The trigger will fire if the state change caused the template to render ‘true’. This is achieved by having the template result in a true boolean expression ({{ is_state('device_tracker.paulus', 'home') }}) or by having the template render ‘true’ (example below). With template triggers you can also evaluate attribute changes by using is_state_attr ({{ is_state_attr('climate.living_room', 'away_mode', 'off') }})

automation:
  trigger:
    platform: template
    value_template: "{% if is_state('device_tracker.paulus', 'home') %}true{% endif %}"

Time trigger

Time can be triggered in many ways. The most common is to specify at and trigger at a specific point in time each day. Alternatively, you can also match if the hour, minute or second of the current time has a specific value. You can prefix the value with a / to match whenever the value is divisible by that number. You cannot use at together with hour, minute or second.

automation:
  trigger:
    platform: time
    # Matches every hour at 5 minutes past whole
    minutes: 5
    seconds: 00

automation 2:
  trigger:
    platform: time
    # When 'at' is used, you cannot also match on hour, minute, seconds.
    # Military time format.
    at: '15:32:00'

automation 3:
  trigger:
    platform: time
    # You can also match on interval. This will match every 5 minutes
    minutes: '/5'
    seconds: 00

Remember that if you are using matching to include both minutes and seconds. Without seconds, your automation will trigger 60 times during the matching minute.

Zone trigger

Zone triggers can trigger when an entity is entering or leaving the zone. For zone automation to work, you need to have setup a device tracker platform that supports reporting GPS coordinates. Currently this is limited to the OwnTracks platform as well as the iCloud platform.

automation:
  trigger:
    platform: zone
    entity_id: device_tracker.paulus
    zone: zone.home
    # Event is either enter or leave
    event: enter  # or "leave"

Multiple triggers

When your want your automation rule to have multiple triggers, just prefix the first line of each trigger with a dash (-) and indent the next lines accordingly. Whenever one of the triggers fires, your rule is executed.

automation:
  trigger:
      # first trigger
    - platform: time
      minutes: 5
      seconds: 00
      # our second trigger is the sunset
    - platform: sun
      event: sunset