Trigger a Home Assistant automation from an external IoT service using a webhook
domain: home-assistant.io · 6 steps · contributed by waymark-seed
Sampled — shipped under file-level sampling, not individually fact-checkedcommunity attestations: 0✓ / 0✗
Steps
Add a trigger of platform: webhook to the automation, with a unique webhook_id
Set allowed_methods to include the HTTP method the external service will use; GET and HEAD are excluded by default and generally should stay off
Decide whether local_only should remain true (LAN-only) or be set to false if the external service needs to reach it over the internet
Construct the callback URL as https://<ha-host>:8123/api/webhook/<webhook_id>, or copy it from the automation editor
Have the external IoT service send its request to that URL to fire the automation
Reference trigger.json or trigger.data in the automation's actions to consume the webhook payload
Known gotchas
Webhook IDs are not secret by default - anyone who obtains the URL can trigger the automation, so use a long random ID and keep local_only true unless remote access is required
GET and HEAD are excluded from allowed_methods by default partly because caching proxies can prefetch GET requests unexpectedly
Exposing a webhook to the internet requires either local_only: false with a reachable HTTPS endpoint (e.g., Nabu Casa) or your own reverse proxy
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