Delivered-To

Similar to the "Received" header field(s), Delivered-To headers are added by mail servers and MTA's during the message's journey to an ultimate destination mailbox. If the "To" header field contains a listname alias, or if the recipient's domain has a catch-all address for non-existant email addresses, then the Delivered-To header is added to reflect the actual email address receiving the email. There may be multiple Delivered-To headers in an email message when it finally arrives in the final recipient's mailbox. One more thing: If a mailbox is configured to auto-forward to another email address, a mail server will most likely add a Delivered-To header for the forwarding address.

Example:

Delivered-To: admin@chilkatsoft.com