A Marketer’s Field Guide to AOL Inboxes

You’ve got mail! After more than a decade, AOL is still a major webmail player in the United States. Most reports rank AOL #4 in total mailboxes behind Microsoft Hotmail Live, Yahoo! and Gmail respectively. The company has a global reach but its presence is about half of the other major players if you count their number of worldwide mailboxes.

AOL’s proprietary filtering technology has always been very sophisticated. In the early days they were transparent with their methodologies but, unfortunately, bad actors exploited that information and AOL became increasingly private about their practices. However, if you are treating your subscribers with respect, by sending them relevant email and unsubscribing them if they are not engaging, then you won’t have a problem getting delivered.

As is typical with many ISPs, the AOL postmaster team is overworked so users (aka “customers”) take priority over senders. If your issues are bulking, you won’t get a lot of attention. However, if you are having issues with whitelisting or feedback loops then you’ll get a relatively quick response. Return Path has always had a solid relationship with AOL and they have been responsive regarding client issues.  One thing to note is AOL is constantly improving their Postmaster and Troubleshooting pages.  They are actively working on automating much of their Postmaster troubleshooting so keep that in mind when reaching out to the team.

User base profile. You won’t see Gen Y or Z rushing out to sign up for an AOL account. Their core subscribers are your parents and grandparents who probably signed up with a floppy disk or CD that they received in the mail. That being said, if their user base is anything like my parents, they are a very loyal and engaged bunch who check their email on a consistent basis.

Spam filtering. AOL’s reputation system is home-grown. As a general observation, if you are a responsible sender and on AOL’s whitelist you will not see a lot of bulking. Our Professional Services team tends to troubleshoot Gmail, Yahoo!, and Hotmail deliverability issues more than AOL.

AOL maintains a very informative postmaster website that is rich with email best practices for senders. This is a hold-over from the early days when AOL was transparent and disclosed more about their filtering technology than most ISPs. If a gold standard exists for guiding senders in their email practices, this is it. It’s well written and a great reference for anyone looking for deliverability tips written in plain English.

Feedback loops. AOL was the first ISP to offer FBLs. As a matter of fact, AOL’s feedback loop set the industry standard for FBL application, security requirements and processing because it was one of the best models for this process. FBL sign-up is easy from their postmaster site.

Prioritized Delivery. AOL offers two levels of free whitelisting: Standard and Enhanced. The Standard whitelist will benefit you for volume thresholds but it won’t get you to the inbox. Approval to this list is based on your sending reputation. We advise our clients to apply for FBLs, build 30 days of sending history, and wait for the IPs to have a “Neutral” or “Good” sending reputation using AOL’s Reputation Check Tool before applying to their whitelist.

Admittance to the Enhanced whitelist can’t be applied for – your IPs will be added and removed dynamically based on your reputation over a 30 day running average. You must, however, be accepted to the Standard whitelist before you can be considered for the Enhanced list. The benefits of the Enhanced service are that you will bypass many of their filters and get delivered to the inbox with images on and links enabled – similar benefits that the Return Path’s Email Certified Whitelist Program offers for most other major ISPs.

Sending reputation. AOL primarily looks at IP reputation with only a cursory look at domain. They offer a Reputation Check Tool to gauge your AOL reputation. The results will yield a simple Good, Neutral or Bad rating. A result of Undisclosed means there is not enough history to calculate a reputation.

Complaints are a primary driver of reputation. If your metrics show that you are sending to active and engaged users then you can get away with more complaints. Conversely, if you are padding your list with a lot of inactives then complaints will be given a higher weighting. AOL does consider users who hit ‘This is not spam’ (TINS) in their reputation calculations. Additional reputation drivers include authentication, spam traps, unknown users, volume and content. AOL maintains their own internal blacklist and they subscribe to the Spamhaus block list.

Engagement. As we said before, AOL has led the industry in many ways. This is also true for email engagement data. AOL has been involved in analyzing engagement for a long time. They analyze who marketers are sending to, calculate reputation from active users and measure complaint rates based on messages in the inbox. Who you are sending your email to will drive your inbox placement rate. We believe that engagement trumps complaints when it comes to determining reputation. The bottom line is to only send to active and engaged users.

Sending Infrastructure requirements. DKIM and SPF should be implemented as a best practice. A double fail of both DKIM and SPF will land your email in the spam folder.

That’s it for AOL. Stay tuned for the next blog in my Email Marketer’s Field Guide series. Have you missed any? Catch up on GmailMicrosoft Hotmail and Yahoo!. And be sure to read the introductory blog here.

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