Requirements
- The active project must contain a verified sending domain.
- Your account must be allowed to send from the project.
- You need at least one valid recipient.
- Use content you are permitted to send to that recipient.
1
Open the composer
Open Emails and select the send action.
2
Add recipients
Enter one or more comma-separated addresses.
Without CC or BCC, Signal treats multiple direct recipients as independent messages so each recipient gets its own status, tracking, and unsubscribe context.
Keep a fan-out request at or below 50 recipients.
3
Choose the sender
Enter a From address whose domain is verified in this project.
Use a mailbox name that matches the message purpose, such as
security@auth.company.com.4
Write the message
Add a non-empty subject and HTML body.
Review every link and visible value before sending.
5
Send and inspect
Submit the message, open its detail page, and follow the timeline.
Do not use the initial accepted state as proof of delivery.
Dashboard scope
The composer intentionally exposes a focused set of fields. Use the Email API when you need plain-text content, reply-to, CC, BCC, attachments, tags, metadata, per-message tracking overrides, scheduling, test mode, or idempotency.Multiple-recipient behavior
Direct To recipients without CC or BCC fan out into separate Signal messages. Each message has its own ID and lifecycle. A request that includes CC or BCC remains one shared message. A topic or segment audience ID must be the only recipient and cannot be combined with CC or BCC.SDK example
After creating an authenticated client with the matching SDK setup guide, use the operation for your language or framework.TypeScript