Add dedicated timer trigger platform for automation editor

[mik-laj]

Describe the feature

Currently, timers in Home Assistant can only trigger automations using an event trigger (platform: event, event_type: timer.finished, etc.).
While functional, this approach is not discoverable for most users and doesn’t integrate with the visual automation editor.

I propose introducing a dedicated timer trigger platform that directly exposes timer events (finished, started, cancelled) in the UI and YAML, similar to the calendar trigger that can react to event start/end times.

Example YAML syntax:

trigger:
  - platform: timer
    entity_id: timer.kitchen
    event: finished

This would internally map to the corresponding event trigger (event_type: timer.finished, event_data.entity_id: timer.kitchen) but provide a clearer and more user-friendly interface.

Use cases

• Allow users to easily create automations reacting to timer completions, starts, or cancellations directly from the visual editor.
• Improve readability and maintainability of YAML automations by using a first-class timer trigger instead of a generic event trigger.
• Provide parity with the calendar trigger that supports “start” and “end” events.
• Reduce user confusion about which event_type names to use (timer.finished vs timer.done, etc.). Ref: How to trigger an automation upon a timer finishing home-assistant.io#29897

Current workarounds

Right now, users must manually create an event trigger with:

trigger:
  - platform: event
    event_type: timer.finished
    event_data:
      entity_id: timer.kitchen

This requires knowing internal event names and makes the trigger configuration unavailable in the automation UI.

Some community blueprints emulate this behavior by exposing timer selection inputs and mapping them to event triggers behind the scenes, but these are only partial solutions.

Anything else?

• A frontend implementation could mirror the calendar trigger UI: users select a timer and choose between “finished”, “started”, or “cancelled”.
• Internally, this feature could remain a thin wrapper around existing event handling, minimizing maintenance cost.
• Similar design patterns already exist for other domains, such as calendar and sun triggers.
• If this proposal gains support, I’m open to implementing it myself and submitting a pull request.

[Petro31]

These types of triggers are coming in the new trigger system. You can get more info over in discord.

[protik77]

Is there any specific thread or conversation that I can take a look at?

Currently there's no triggers when a timer is finished.

[nielsrowinbik]

They haven't been implemented yet, but they will be as part of home-assistant/core#158350!

[decoder12]

Hello, I pointed this out in my post a while ago. Today I would also add the inability to read the remaining time of the timer from the coding level. going further, it would be useful to have a clock time for the timer to end (now I looking for way to calculate it).
https://github.com/orgs/home-assistant/discussions/851

[mik-laj]

Hi! it’s actually possible.

When a timer is active, it already provides a finishes_at attribute, which you can use both to calculate the remaining time and to know the exact end time.
For paused timers, you can read the remaining attribute, but it doesn’t update dynamically.

If you want to display exact end time:, you can calculate it like this:

state_attr('timer.night_lights_in_marlenka_bedroom', 'finishes_at')

And if you also want the remaining time, you can calculate it like this:

{{ (as_datetime(state_attr('timer.night_lights_in_marlenka_bedroom', 'finishes_at'))- now()).total_seconds() | timestamp_custom('%H:%M:%S', false)   }}

For dashboards, some community cards (like timer-bar-card) already handle this visually using the finishes_at attribute.

[nielsrowinbik]

There was another recent similar feature request, and so I've added an issue to add a trigger for the remaining time on a timer here: home-assistant/core#164338.

[protik77]

Right now using timers is the only way to persist an automation in case of a Home Assistant reboot when waiting for an event. Adding this to the UI will be valuable for the community in general.

[nielsrowinbik]

Timer triggers are coming as part of the new trigger system (currently in labs). Those interested can follow along in this issue: home-assistant/core#164338.

[mik-laj]

This change has been related in 2026.05b1 https://rc.home-assistant.io/blog/2026/04/29/release-20265/ but it has teething problems: home-assistant/frontend#51813