Imagine a row of houses are built and mailboxes are placed in front of each house. After a period of time, those same houses are no longer occupied, and the houses are knocked down–would you keep sending mail to the mailboxes? In the email world, senders face a similar decision when they have email subscribers that have not shown engagement with their emails over a period of time. 

What is an email sunset policy?

Many email marketers that live and breathe email understand the importance of implementing a sunset policy. Sunsetting is the strategy of reducing the number of emails recipients receive (or dropping recipients from your list altogether) when they haven’t engaged with your messages after a set amount of time. The problem usually lies when that same email marketer tries to get buy-in from upper management, or a sales team, that they will be sending less email. 

Why is sunsetting email contacts important?

For those outside the email world, database size is usually the biggest concern, and a plan to reduce database size is usually met with pushback. The focus needs to shift from “how many people are we sending emails to?” to “how many people are opening our emails?” 

Once that focus shifts to engagement data rather than database size, the concept of a sunset policy starts to make more sense. It’s also vital to understand that sunset levels are unique to each business. How often you send and what types of emails you send play a big role in determining your sunset levels. More information can be found on that here.

Continuing to send to old, inactive email addresses will do a few things:

  1. Lower your overall engagement rates
  2. Annoy subscribers and lead to increased spam complaint rates
  3. Increase the number of spam traps you send to

All of these elements result in one thing: a decreased chance of your emails making it to the inbox. So the question needs to be asked, what are the benefits of continuing to send to old, inactive email addresses? Outside of being able to report an inflated number to advertisers, there really isn’t any advantage. 

How to sunset your unengaged contacts

An important exercise to do is to split your database into engagement segments and determine unique open rates from each bucket. For example, engagement buckets could be anyone who has opened an email within the last 30 days, 31-60 days, 61-90 days, etc. 

Then, once you send the same email to each bucket, observe the unique open rates for each group. For the vast majority of senders, you’ll see a drastic reduction in open rates with each engagement bucket. 

Here is an example of one such exercise:

As we can see from this example, this brand does a great job with sunset levels. Between 80-90% of emails are sent to subscribers that have opened an email within the last 30 days. We can see the drastic reduction in open rates for subscribers that last engaged 31-60 days ago, 61-90 days ago, etc.

If we take one day, March 3rd, as an example, the open rate for the 0-30 group was 8.2% and the open rate for the 31-60 group was 1.1%. Are the handful of opens you see from sending to an audience that hasn’t engaged in 90-120+ days worth risking spam placement for emails sent to your engaged audience? To most of us, it is not worth the risk.

After you share this information with any skeptical decision-makers, hopefully, you have buy-in to at least test out sunsetting your least engaged subscribers. You don’t have to sunset all old, inactive email addresses at the same time. Identify 10% of your database that hasn’t opened in over 6 months and start with that group. This will allow you to improve your reputation, but not take a big hit on database size. 

Email sunsetting example

We used a similar approach for a customer that also faced buy-in issues for sunsetting. As we rolled out sunsetting for the oldest, least engaged subscribers, we saw overall unique open rates steadily increase over the year. These improved metrics sent more positive signals to inbox providers in regard to their traffic. 

We continued sunsetting more groups until they got to a point where a majority of their sends were going out to an audience that opened emails within the last 6 months. The end result? 

They doubled their unique open rate from the beginning of 2020 to the end of 2020. They also saw a 65% reduction in the number of spam traps hit on a daily basis. With the reduction in spam trap hits and the increase in engagement rates, they saw a big improvement in emails landing in the inbox rather than the spam folder. Even though they sent to fewer subscribers as the year went on, they saw their unique opens and clicks increase drastically. 

Sunset policy takeaways

When it comes to email success, the focus needs to shift from database size to unique opens. Let’s review a few reasons why:

  1. Inbox providers want to protect their users’ inboxes from brands that flood their inboxes with unwanted mail. 
  2. If a brand does not sunset unengaged subscribers, it is likely that the inbox provider will deliver those emails to the spam folder. 
  3. There is no point in sending to a large database of subscribers that do not open your emails. Sending to unengaged subscribers hurts your chances of landing in the inboxes of interested and engaged subscribers. 

When the focus shifts from database size to unique opens and landing in the inbox, sunsetting becomes a no-brainer. 

If you’re unsure how to approach an email sunset policy, work with our email deliverability experts to discuss the best strategies for your brand. 



Denis O'Sullivan
Denis has been working in the email marketing space for 12 years. Most of that time was spent managing email programs for various brands. A native of Ireland, Denis spent most of his life in Florida before moving to Colorado. Denis enjoys exploring his new state with his family.