AT&T Email Best Practices & Guidelines

AT&T Postmaster Website

Email Best Practice Guidelines



AT&T requires that all email sent through its servers follows the AT&T email guidelines as well as any applicable federal, state, and local laws. Following the email guidelines does not guarantee that your email will be delivered; however, it should decrease the chances of your email being misidentified and blocked as unsolicited bulk email or spam.


AT&T email guidelines: best practices for email senders


The following guidelines will help ensure that your email will be delivered through the AT&T mail servers. If these requirements are not met, your messages may not be accepted.


  • Ensure that your email follows all appropriate Requests for Comments (RFCs). http://www.rfc-editor.org
  • Ensure that all email complies with the Federal Can Spam Act of 2003. http://www.spamlaws.com/federal/can-spam.shtml
  • Deliver email through your ISPs mail servers, if available. Connecting directly from a dial-up or other dynamically assigned IP address is possible, but it may result in your mail not being delivered.
  • Separate large quantities of email into sections and deliver at periodic intervals.
  • Send messages only from IP addresses that do not appear on any Real-time Blackhole list (RBL). Connections and messages from an IP address listed under a reputable RBL may not be accepted. To have your IP address removed from an RBL, contact the list’s manager directly.
  • Do not send email from an IP address where the sender’s identity changes often.
  • Include proper header information on all email messages.
  • Do not send messages that result in too many concurrent simultaneous connections to our mail servers.
  • Do not attempt to discover email accounts by sending messages to the AT&T mail server. Servers making this attempt will be blocked by AT&T, and further legal action will be taken.