Suppression Lists

To maintain favorable reputations with mailbox providers, our system reviews recipient lists and automatically suppresses email addresses for the following reasons:

  • Hard bounces — When email delivery fails, mailbox providers send bounce code responses. The system categorizes and tracks these bounce codes so that it can suppress email addresses when they fail, such as when a recipient's address is invalid or their account is closed.

  • SPAM complaints — Our email specialists help maintain Feedback Loop (FBL) agreements with mailbox providers that offer FBL programs. With an FBL agreement, a mailbox provider agrees to inform us when a recipient marks a message as unsolicited — such as when they select a "This is SPAM" button or link — so that our system can suppress their email address from future mailings from that sender.

    Note: If the same email address appears in the recipient list for a mailing from another Blackbaud client, our system does not suppress it unless the recipient also marks the message from the other client as unsolicited.

  • Opt-out links — When a recipient uses an opt-out link in a message to request removal from emails, our system suppresses their ddress from future mailings specific to their request, such as only for a particular newsletter or all emails from an organization.

    The system also supports unsubscribe requests from links that some mailbox providers — including Gmail and Outlook Mail — add to the top of messages. When recipients select these links rather than report your message as SPAM, there’s no negative impact to your sender reputation with the mailbox provider.