List Acquisition and Email Validation Part 1 – Strategic Background

While list acquisition and email validation may seem like minor issues, it actually has a severe impact on your ability to reach the inbox.  Proper list acquisition needs to be at the center of your email marketing strategy to ensure highly engaged subscriber and best data quality up front at the point of sign up already.

How Data Quality impacts Deliverability
Data quality is becoming one of the two central factors in email filtering for mailbox providers such as Gmail, Microsoft, and Yahoo.

When deciding to accept or reject incoming email, mailbox providers focus on complaint rate, list hygiene (mainly driven by hard and soft bounces) and user engagement. This puts pressure on the email marketer’s strategy.

What happens if email validation and technical list cleansing are not implemented? This is shown by  this IP address reputation graph:

Impact of Unknown User on Sender Score:

Although the recommended 30-days level for unknown users is 1.3 percent, this client experienced rates up to 10 percent (shown by the blue line in the graph above). These rates impacted their Sender Score (green line). This ends up in lower deliverability as mailbox providers start to filter email campaigns because of bad list hygiene practices and missing email validation techniques.

But, even if technical checks are properly set up and the acquired data is clean from unknown users, it can still be the case that subscriber expectations are not properly set or misaligned to the personal understanding of the user. What happens when the expectations of email frequency, content, or design do not match the subscriber’s view can be seen with this graph where complaints are above the ideal 30-days average of 0.46 percent (blue line in the graph below).

Impact of Complaints on Sender Score:

Third Party versus Organic List Acquisition
List size is an important KPI to for email marketers, but it’s important to be careful about how you are acquiring new emails.  Either using third party email list vendors or growing the email list through organic sources depends on business goals and is a challenge every email marketer needs to deal with.

While third party acquisition methods such as list rental, co-sponsoring, or standalone campaigns will grow the list quickly, it will not ensure a high-quality performance in user engagement, such as read rates, open rates, click-through, and conversions. The risk of higher unknown user rates and spam traps are very high using this list acquisition method.

Organic list growth ensures a better quality of data and much higher engagement. Also, the risk of adding pristine spam traps and unknown users is much lower than growing the list through third party sources.

Whatever way you choose to grow your email list, you should always consider the basic fundamentals:

  • Clearly lay out the benefits
  • Permissioning is front and center
  • Simple opt-in form design 
  • Be mindful of the mobile experience
  • Keep required fields to a minimum
  • Set expectations about the email program
  • Email-exclusiveness to increase the value
  • Include confirmation/ welcome messaging
  • Consider using a list validation service

As always in email marketing, the key factor is setting the right goals for list acquisition, because they drive the motivation and strategic approach. List growth will be the central goal forever, as well as winning leads and new sales, but adding goals as avoiding unknown users, spam traps, and spam complaints will change the game and make email marketing profitable and reduce the risk of being filtered out by the mailbox provider.

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