> ## Documentation Index
> Fetch the complete documentation index at: https://docs.custral.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Suppressions

> Bounce, complaint, and unsubscribe handling.

A **Suppression** records that Custral must not send to a particular address again. Suppressions are workspace-scoped, per-channel-type, and outweigh any subsequent send attempt: even a manual one.

## Sources of a suppression

| Source                    | Trigger                                                                                           |
| ------------------------- | ------------------------------------------------------------------------------------------------- |
| **Hard bounce**           | The receiving mailbox permanently rejects the message (mailbox not found, domain does not exist). |
| **Soft bounce, repeated** | Three or more consecutive soft bounces (mailbox full, temporarily unavailable).                   |
| **Complaint**             | The recipient marks a message as spam and the provider reports the complaint back to Custral.     |
| **Unsubscribe**           | The recipient clicks the unsubscribe link or replies `STOP` (SMS).                                |
| **Manual**                | A user adds the address from the Channel settings page or the API.                                |

## Lookup before send

Every outbound send checks the suppression list first. If the recipient is suppressed for that channel type, the send is stopped and the failure is recorded on the Conversation timeline as suppressed. This applies to manual sends, sequences, and workflow actions equally.

## Removing a suppression

A user with admin permission can remove a suppression from the Channels settings page. Removing a suppression added by **complaint** is rarely safe, the recipient explicitly flagged you as spam.

<Warning>
  Removing an unsubscribe suppression so you can re-mail someone is, in many jurisdictions, a regulatory violation
  (GDPR, CAN-SPAM). Be sure you have a valid reason to override the user's choice.
</Warning>

## Per-channel-type vs per-channel

Suppressions are scoped to channel **type** (`email`, `sms`), not individual channels. An email address suppressed via Mailbox A is also suppressed when sending from Mailbox B. This prevents a contact who unsubscribed from one of your sender personas from receiving mail from another.


## Related topics

- [Email](/data/properties/text/email.md)
- [Sending SMS](/comms/sms/sending.md)
- [Run an outbound sequence](/recipes/outbound-sequence.md)
- [Templates](/comms/templates/overview.md)
- [Troubleshooting](/comms/deliverability/troubleshooting.md)