---
ref: tool:customer-io/trigger-broadcast
name: Trigger a broadcast
company: company:customer-io
workflows: []
access: [api]
tags: [capability:send-email, category:email, has:api]
docs: https://docs.customer.io/integrations/api/app/tag/send-messages/triggerBroadcast/
updated: 2026-09-27
---

# Trigger a broadcast

Sends an API-triggered broadcast now or at a scheduled time, to its saved audience or to the people, emails or filter you pass, with data for its Liquid placeholders.

Set the broadcast up in Customer.io first. It reaches only people already in
the workspace: unknown recipients fail the request unless you set
`email_ignore_missing` or `id_ignore_missing` to `true`. Reference `data` in
the message as `{{trigger.<key>}}`. This endpoint allows one request every 10
seconds.

## Set up

Use the first option your agent supports.

### API (official)

- Base URL: https://api.customer.io
- Endpoint: `POST /v1/campaigns/{broadcast_id}/triggers`
- Auth: send the header `Authorization: Bearer $CUSTOMERIO_API_KEY`
- Get a key: https://fly.customer.io/settings/api_credentials?keyType=app
- Docs: https://docs.customer.io/integrations/api/app/

Before doing anything else, make one read-only call to confirm access.

## Rules

- Ask the user before anything that sends messages, costs money, or changes data.
- Never print API keys.