Suppression lists

Suppression lists are a special type of subscriber list. There is only one per client, and it contains email addresses you don't want to send to, to help protect your sending reputation. Email addresses on a suppression list can't be accidentally imported or added to your regular subscriber lists.

Below, we'll explain how email addresses are automatically added to a suppression list, and how you can suppress email addresses yourself. This comes in handy if you've previously maintained a "do not email" list in an external tool, or switched to us from another email service provider.

Email addresses on suppression lists don't count towards your monthly billing, unless they are also active on regular subscriber lists.

Automatically added addresses

A subscriber's email address is automatically added to a suppression list if:

The address hard bounces.
The subscriber marks one of your emails as spam (unless they are on Gmail).
The subscriber unsubscribes, or you set their status to unsubscribed.
It was part of a bulk remove operation, with the "Unsubscribe from all lists" option selected.

When viewing a suppression list, the reasons for the above items will be shown as either "Unsubscribed", "Marked as Spam" or "Bounced".

If the list Unsubscribe option is set to "Remove subscriber from this list only", the subscriber will not be added to your suppression list.

Manage suppression lists

To access suppression list, you must have at least one subscriber list. Then, to manage it:

Click Clients in the top navigation, then select the relevant client.
Click Lists & subscribers.
Click Suppressions on the left menu.

You will then see the suppression list, and the reason each email was added to the list. If they were added automatically, the reason will be "Unsubscribed", "Marked as Spam" or "Bounced". If you see "Suppressed", it means the email address was added manually.

The suppression list, with email addresses added to it, and the tools to manage it

To export a suppression list, in CSV or tab delimited format, select Export list, above the table.

Add email addresses

To manually add email addresses to a suppression list, click Add to suppression list on the top right side of the page, then follow the instructions.

Email addresses added in this way will have the reason "Suppressed".

There are two ways you can add to suppression list:

Enter email addresses – Enter or paste each email address on a new line.
Import a file – Drag-and-drop a file from your computer or click upload a file. The file should have one column containing email addresses.

You can add up to 50,000 emails at a time.

Remove email addresses

To remove email addresses from a suppression list, select the checkbox to the left of the email addresses you want to remove, then click Remove from suppression list.

When removing an email address from a suppression list, you also need to change its subscriber status back to "Active" for the list it was on. Learn how to resubscribe an unsubscribed email.

Suppression list overrides

Email addresses on a suppression list can still be added to a subscriber list, if subscribers:

Sign up again after unsubscribing, through a signup form.
Are added or updated via the API with resubscribe set to true.
Have their status changed from "Bounced", "Marked as Spam" or "Unsubscribed" to "Active".
Select a preference center link in an email campaign, generating an email with a secure sign-in link to update their subscription preferences sent to their inbox

These methods bypass a client's suppression list for the chosen subscriber list only. The email address will remain on the suppression list, to prevent it being accidentally imported or added to other subscriber lists.