---
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.

Note: Set the broadcast up in Customer.io first. Unknown recipients fail the request unless you set `email_ignore_missing` or `id_ignore_missing` to `true`, and the 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 anything else, confirm access with the cheapest read-only call, like a list or a search. Never send or change anything to test access.

## Rules

- Ask the user before anything that sends messages, costs money, or changes data, and say how many records it touches. One approval covers a batch the user has seen.
- Never print API keys.