When we onboard enterprise customers here at SparkPost, one of the topics we cover is list hygiene: removing inactive users from your mailing list. The definition of “inactive” really varies by email type (marketing, welcome, transactional) and industry (finance, marketing, employment, etc). For example “inactive” in the employment industry could be six months or more, meaning if a user seeking a new job has not opened or clicked on a piece of email sent by your company in half a year, they are considered inactive. But, for a company like Pinterest inactive could be 12 months, as some users might only check Pinterest during the winter months to get outfit ideas for their company’s annual holiday party. So, there is no hard and fast rule when it comes to defining “inactive” in the email marketing world.

The challenge is to convince the CRM team to remove inactive users as there can be push back since many see each email address a possible source of revenue. But, the risks of sending to a large population of inactive users are greater than keeping them for the sake of possible revenue.

Here’s why:

  1. ISPs turn old email addresses with no activity into spam traps after 12 months. Hitting too many traps will result in a lower IP/ domain reputation.
  2. Major ISPs take engagement into consideration for inbox placement. If a high percentage of the email addresses on your list have zero open rates in the past 12 months, this is an indication of poor list hygiene which will result in heavy spam foldering.

The truth is if you are sending email to the people who want to receive them, they have a higher chance of engaging with your emails. If they are not opening your emails, even if they signed up for them at some point, it means they are no longer interested. There is little benefit to keeping sending them on your list because there is a high chance that they will get annoyed with your company and could report your email as spam. A high complaint rate will damage your reputation. And, even if there is a small chance that a low percentage of these subscribers will open an email after 12 months of inactivity, the risks of hitting a trap are much greater than the revenue that can be generated from that user.

~ Kate