Understand email contact suppression reasons

Learn what each contact suppression reason means and what causes a contact suppression.


Your email contacts can be suppressed for different reasons. Suppressions can happen intentionally or unintentionally. Each suppression is labelled with a reason, and in this article, we’ll tell you what each reason means.

Suppression reasons

Suppression type Details
Soft bounced

The contact's email address is temporarily unreachable:

  • The contact's inbox is full.
  • The server that hosts the email address is having temporary problems accepting emails.
  • The email campaign is too large for the contact's inbox.
A soft bounce suppression happens once a contact reaches the soft bounce limit that's set by you or a managed user in your account. To learn more about setting a soft bounce limit, check out Adjusting soft bounce settings.
Hard bounced

The contact's email address is permanently unreachable:

  • The email address doesn't exist anymore.
  • The server that hosts the email address doesn't exist anymore.
  • The email address is invalid.
Unsubscribed The contact is unsubscribed from your email campaigns:
  • The contact selected the unsubscribe link in your email campaign.
  • You or a managed user unsubscribed the contact.
    To learn more about manually unsubscribing a contact, check out the article Unsubscribe a contact.
  • The contact is unsubscribed after running a Global Suppression List (GSL) check.
    To learn more about the GSL, check out Using the Global Suppression List (GSL).
Suppressed by you

You or a managed user suppressed the contact in your account.

To learn more about manual or file contact suppressions, check out Suppressed contacts and domains.
ISP complaint The contact marked your email campaign as spam.
Mail block The contact's email provider doesn't want to process email campaigns from you, likely because of the attachments in your campaigns.
Direct complaint The contact made a direct complaint to us, and we suppressed this contact in your address books.
Globally suppressed Contacts who've either complained directly to us in the past or are known spam traps or invalid addresses.
Domain suppression Contacts whose email domain you have previously added to your suppression list.

Hard and soft bounces

Hard bounce vs soft bounce

A hard bounce is an email sent to contacts whose addresses are permanently unreachable, most likely because they, or the server they were hosted on, don't exist. The email address is invalid. A hard bounce will immediately result in the email address being placed in the suppression list.

A soft bounce is an email sent to contacts whose addresses are temporarily unreachable, possibly because their mailboxes are full or their mail servers are having temporary issues accepting email. It doesn't necessarily mean the email address is invalid.


If an email address hard bounces once, or soft bounces too many times, it will be suppressed in your account to prevent you from sending to it. This helps to protect your sending address and server from being blocked for spamming.

The platform allows you to set how many times a contact can consecutively soft bounce before they become suppressed in your account.

To learn more, check out the article Adjusting soft bounce settings.

Types of bounce response

You might sometimes see a bounce response for a contact with some additional information about the type of bounce:

  • Soft bounce - DNS failure: Although we tried several times, we were unable to determine which mail server is configured to accept mail for this email address. This may be due to the correct mail server undergoing maintenance at the times we attempted to send the message.
  • Soft bounce - mailbox full: The recipient's mailbox is too full to accept the message you tried to send them.
  • Soft bounce - message too large: The recipient's mail server won't accept a message of this size.
  • Bounce - no email address: A bounce came back, but the mail server we sent the message to didn't indicate who the bounce was on behalf of. We've identified the intended recipient, based on the content of the message being returned.
  • General bounce: The mail server returned the message to us, but didn't indicate a reason why.

Suppressed vs unsubscribed contacts


Unsubscribed contacts

Unsubscribed contacts have decided they no longer want to receive some or all of your communications. Contacts can unsubscribe from individual marketing preferences or address books, or from all of your communications. You can also manually unsubscribe a contact. They are added to the account suppression list with the suppression reason Unsubscribed.

To learn more, check out the article Unsubscribe a contact.

If you resubscribe a contact who has unsubscribed, they are sent a resubscribe confirmation email, and must confirm their resubscription using the link in the email. If the contact doesn’t do this, they remain on the suppression list.

Suppressed contacts

When you suppress a contact, they are added to the account suppression list with the suppression reason Suppressed by you, and they no longer receive any communications from your account. You can think of suppression as a Do not contact status.

Suppressing a contact can only be done by you or a member of your team; contacts can't suppress themselves. You can unsuppress a contact manually at any point.

To learn about the different ways to suppress contacts, check out the article Suppressed contacts and domains.

If you resubscribe a contact who has been Suppressed by you they are immediately added back into your All contacts list, without the need to confirm this through a resubscribe link in an email.

View a suppressed contact’s suppression reason

Go to Email > Contacts > Suppressed contacts to access contact suppressions in your account. The suppression reasons are located under the Reasons suppressed column.


You can filter the suppression list to show only contacts with a specific suppression reason.

To do this:

  1. Select FILTER in the top right.
  2. In the Filter suppressed contacts side panel, expand the drop-down menu and select the suppression reason you want to display.
  3. Select APPLY.

Email reports

To view bounced emails, unsubscribes or ISP complaints for a specific campaign, go to Analytics > Channel analytics > Reports: Email and select the campaign name and then expand the MORE REPORTS drop-down menu to view the relevant drilldown report.

Automatic unsuppressions

If a contact on the Global Suppression List (GSL) engages with any email campaign:

Additionally, contacts are removed from your account’s suppression list after a year if they were suppressed because they reached your soft bounce threshold.

When contacts are unsuppressed for any of these reasons, they aren't automatically added to your account - but they can be created or uploaded again.

See also

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