A list of email addresses to whom delivery of email should not occur. A suppression list is often used by senders using multiple email marketing platforms and/or multiple email marketing channels to maintain consistency between removal requests from different systems. A suppression list can also be used to inhibit delivery to problematic addresses or domains which may be causing complaints or other undesirable effects by sendint to them. Sophisticated email service providers automate the specification of suppression lists and often offer multiple levels of suppression lists to provide the highest level protection.

A list of email addresses that should not be mailed to any longer (kept by a single organization). Usually owners of the addresses on the list have specifically requested inclusion. Required by CAN-SPAM.

A list of email addresses whose owners have asked to be removed from an email list so that they longer receive email regarding an advertiser's products or services. A reputable email marketing service makes this process automatic, however, if you use multiple email products, or have multiple databases from which you send emails, you should use a suppression list to process all unsubscribe requests across all lists.

A list of email addresses kept by a single organization that should not be mailed to any longer. Usually owners of the addresses on the list have specifically requested inclusion. Required by CAN-SPAM.