Postmaster Best Practice Guidelines

This page contains AOL's best practice guidelines for email senders. While following all these guidelines will not guarantee that your email will be delivered, it should decrease the incidence of your email being misidentified as unsolicited bulk email (spam).

Best Practice Guidelines

  • Any email sent to AOL members must conform to AOL's Bulk Communications Policy
  • All email must be RFC compliant (please refer to for more information about RFCs pertaining to email).
  • All email servers connecting to AOL's relay servers must have valid reverse DNS entries (i.e. all sending IP addresses must have active corresponding domain names in DNS).
  • All email servers connecting to AOL's email servers must be secured to prevent unauthorised use (they may not be an open proxy or an open relay).
  • Connections from dynamically assigned IP addresses (dial-up accounts) will not be accepted to AOL's relay servers.
  • Organisations may not hardcode AOL's MX records into their configuration files.
  • Organisations must immediately unsubscribe any AOL email addresses that receive a permanent failure email bounce from AOL's mailer-daemon.
  • Any URL or link contained in your email should contain a domain name. For example, a link to is confusing and might not be recognised by your recipient.
  • Please avoid the use of virtual servers in your links if possible.

Additional Best Practices Guidelines for Commercial Email

  • Organisations must not do anything that tries to hide or forge the sender of the email and the sending site of the email.
  • Each mailing should specifically state how the AOL members' email addresses were obtained (i.e. purchase from Acme tools, sign up for travel discounts, etc.) and must state whether this is a one-time mailing or a reoccurring mailing. Additionally, such details as the date and time when the email address was obtained, along with the IP address, must be available upon request.
  • All mailing should contain simple and obvious unsubscribe mechanisms. While we recommend that this be in the form of a (working!) link to a one-click unsubscribe system, a 'reply to:' address may also be used. In this case we require that the address receiving those replies be valid.
  • All email must have valid non-electronic contact information for the sending organisation in the text of each email (phone number, physical mailing address, etc.). If this is not readily feasible, there must be a link in each email to such information on the sending organiation's website.
  • Senders should ensure that the sender email address and subject line wording are not likely to confuse the recipient into reporting as spam email from a source to which they have opted in. Clear and obvious wording will help the recipient distinguish legitimate emails from spam.