Unsubscribe sources

The article provides an overview of unsubscribe reasons with their explanations and the impact on ability to send system / trigger emails.

All marketing campaigns are sent only to confirmed users by default, but you can adjust segment conditions and reach unsubscribed users.

Unsubscribe ReasonUnsub Source IDExplanationReject AppliedTriggerSystemDocumentation
UNSUB_SOURCE INVALID10Invalid email address / user mailbox does not exist.invalid Unsubscribing for other reasons
UNSUB_SOURCE MX_INVALID12Invalid sender domain (part of the email address after @ symbol).invalidUnsubscribing for other reasons
UNSUB_SOURCE DISTANCE_BOUNCE15Mail server cannot accept this email (user mailbox is full, or account is blocked).invalid-
UNSUB_SOURCE CLIENT_CALLBACK8The user has been removed from the project or unsubscribed in the client's system.unsubscribeUnsubscribe
UNSUB_SOURCE SETTINGS_TYPES9The user unsubscribed through the product settings (e.g. all checkboxes are unchecked in the account).unsubscribeUnsubscribe users from email types
UNSUB_SOURCE FBL2The user was unsubscribed due to spam complaints to the mail server.unsubFBL + exception not_skip_reject fbl_by_mail_type-
UNSUB_SOURCE LIST_HEADER5The user unsubscribed through the email header via the mail server.unsubscribeUnsubscribing for other reasons
UNSUB_SOURCE ADMIN16The user unsubscribed through the Sendios admin panel.unsubFBL + exception not_skip_reject fbl_by_mail_type
The user unsubscribed through the Sendios unsubscribe page (unsubscribe link in the email's footer). If the user has only unsubscribed from marketing campaigns, the rejection does not take effect (the user is just not included in the marketing selection).unsubscribe Unsubscribing via the link in the email
N/AN/AUnsubscribe from a specific type of email, rather than from the entire category. In the admin panel, a specific type will be displayed without the unsub_source.unsubByType❌ (specific type)Unsubscribe users from email types