Poor Deliverability Cause #4: Poor List Quality

This is part five of our six-part blog series addressing the top five common causes of poor deliverability. Click here to start from the beginning.

Maintaining a high-quality subscriber list is imperative to ensuring your emails are delivered to the inbox instead of the junk or spam folder. In addition to complaints, there are three other major culprits of poor list quality: spam traps, unknown users, and inactive users.

Spam traps are email addresses that don’t belong to active users and are used to identify both spammers and senders with poor data quality practices. Hitting a spam trap is an indication that the sender either acquired the email address through questionable means or is a legitimate entity with poor list hygiene. There are two types of spam traps—recycled or pristine—and both can have a major impact on your deliverability. Read our blog for tips to avoid and remove spam traps from your list.

An unknown user is a recipient that either never existed, has been terminated by the mailbox provider, or was abandoned by the end user. Mailbox providers will return a hard bounce code indicating when email is sent to an unknown user. All unknown users should be removed from your file immediately via bounce processing. Learn more about proper bounce processing in our ebook, The Email Marketer’s Guide to Bounce Processing.

Inactive addresses represent customers on your list file who have not opened, clicked, or taken some kind of action for a significant amount of time. Inactive subscribers are undesirable for many reasons. Not only could these addresses be a source of unknown users or spam traps, but they also bring down response rates for the entire program. This negatively impacts your overall reputation and has negative effects on your deliverability.

To learn more about how to identify inactive subscribers, as well as how to improve your overall list quality, download our ebook, The Ultimate Guide to Email Deliverability.

Stay tuned for part six, where we’ll talk about the fifth possible cause of poor deliverability, lack of email authentication.

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