I recommend cleaning your email list every three months to start. Think of it as your quarterly cleaning. As your list gets bigger, shorten the intervals between scrubbings to keep up with the increase in volume.
In addition to setting specific timeframes for email list cleaning, you should also watch out for red flags that indicate your list is getting a bit bloated.
For example, your Open Rates Are Lower Than Ever. A low open rate suggests that many of your subscribers don’t want to read your marketing messages. There are many reasons that this happens; they may have selected another provider, already bought your product, or simply don’t need the service any longer. However, the reason doesn’t matter because you can’t control it. But, you can limit the fallout by cleaning your email list.
Before You Start Cleaning Your List, Check for Hard and Soft Bounces. There are two types of bounces in email marketing: soft and hard. A soft bounce indicates a temporary deliverability issue. Your email service should attempt to send the email again, and it will most likely go through.
Hard bounces, however, are bounces that never go through. The email address is wrong, the domain no longer exists, or the email server has blocked delivery.
Many email services will automatically clean hard bounces. Others will force you to clean your list to get rid of addresses.
Dr. Elijah Clark (August 23, 2021). Cleaning your email list of leads [Web log post]. Retrieved from https://elijahclark.com/lesson-133/