How to Remove your IP from ATTs Blacklist


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As with all of our articles on email blacklist management – we assume you are being a responsible email netizen and not sending spam.  And we also assume you’re probably an Email administrator.   If you’re an individual and you’re having email delivery issues, you’ll probably need the help of your IT team to get access to some of the information here.  Better yet – send them to this link directly.  

If you are having delivery issues with other domains too (and you’re not sending spam) then this article will help you determine if your email servers are on other email blacklists.  Of course you could move your email campaigns to an email service provider like Pinpointe and let us deal with delivery so you don’t have to waste your time dealing with blacklists!

AT&T Email Domains

AT&T manages email inboxes for nearly a dozen domains.  Here are the main domains maintained by AT&T email services – so if you’re seeing emails being blocked to any of the domains below, then you can apply these steps to verify and request removal from the AT&T blacklist:

Verify Emails Blocked by AT&T

AT&T relies on several sources to decide whether to deliver your well-crafted emails are spam (or if your email server’s IP address has a history of sending what AT&T believes is spam.)  AT&T doesn’t maintain a blocklist that you can query directly any more (Updated as of 2020) – instead you will see messages in your sending log files. You’ll know if you are being blocked in one of these ways:

1) If your email servers are blacklisted at AT&T, you will get a bounced email  (called a ‘NDR’ – non-delivery report’) with an error code 521 – indicating a mailing was blocked because it ‘exhibited behavior consistent with spamming or abuse.’  The NDR email will include information something like this (Note: The exact error message will vary depending on your email client) :

Reporting-MTA: dns;
  Final-Recipient: rfc822;

Action: failed
 Status: 5.5.0
 Diagnostic-Code:  Remote_host_said:_521-xx.xx.xx _blocked_by_ldap: ou=rblmx,dc=AT&T,dc=net/521_Error_-_Blocked_for_abuse._

2) You can also check your email server logs for rejection messages.  The most common error messages are:

521 xx.xx.xx.xx blocked by DNSRBL: Blocked for abuse. See, (

553 5.3.0 alph740 DNSBL:ATTRBL 521< xx.xx.xx.xx >_is_blocked.For assistance forward this error to

550 xx.xx.xx.xx  blocked by ldap:ou=rblmx,dc=att,dc=net Error - Blocked for abuse. See"
  Note: 'dc=' will include the recipient domain, like att, bellsouth, etc.

Removal from AT&T Blacklist

As we’ve noted in all our posts regarding blacklists – as a reputable  email service provider for businesses , we have to start with the obvious: be sure you’re not spamming before you make your request.  If you or your company are sending unsolicited emails or general spam – you’ll need to clean up your internal practices before taking the steps below.  SPAM filters are really pretty smart these days so if you are actually spamming and your removal request is honored, you’ll be right back on the list again in a few days.  And some blacklists only allow you to request removal every so often.

AT&T first recommends you check your email server’s IP address on these two blacklists – and if you happen to be on either of these – take the steps to remove your server from these first (most places will block email if you are on a spamhaus blacklist.)

Once you’ve cleaned up everything and confirmed you are not in fact spamming, you can request removal via email. You’ll need the following information:

  • IP address of the sending server
  • Your IT admin’s name, company, phone and email address.
  • The exact error message from the NDR email or the email server logs.
  • An explanation of the steps you (or your IT team) has taken to stop spam.

Now send your request to the address abuse_rbl @ with the following information:

Subject: IP {your IP} is blocked

Content: -- assuming you are not sending spam:

Hello, we are sending consent based / opt in email from {who you are sending from - send-from address} and our emails are being blocked for {IP address}. We are receiving the response message below:

Please remove the block from our IP and sender. 

Thank you

(Be sure to sign from a real person, preferably IT and the email should be sent from the same domain that is being blocked)

Once the above info is submitted – we’ve found that AT&T resolves any issues within 24 – 48 hours.

For more information about AT&T’s email best practices and mail delivery issues visit:

Consider an Email Service Provider

If your marketing team is sending permission-based email campaigns and/or wants to automate your emails with autoresponders or trigger campaigns, consider using an email service provider like Pinpointe.  Pinpointe manages deliverability and blacklists 24×7 so we can maintain one of the highest inbox delivery rates for customers.  We monitor email delivery on an ongoing, real-time basis and ensure that you’re opt-in emails won’t get blocked.  You can sign up for a free trial any time – .



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