/ Glossary — List & Compliance
What is a sunset policy?
The rule that retires subscribers who've stopped engaging, before they drag down your reputation. Counterintuitive, but pruning your list is how you protect it. Here's why.
/ Definition
A sunset policy is a rule that automatically stops sending to subscribers who have been inactive for a defined period — no opens, clicks, or other engagement over, say, the last few months. Rather than mailing them indefinitely, you retire them from your active list, either pausing them or removing them entirely after a final re-engagement attempt.
It exists because mailbox providers increasingly judge reputation on engagement: mail to people who never open it signals that your list isn't wanted, which hurts inbox placement for everyone. Worse, long-abandoned addresses can become recycled spam traps. A sunset policy prunes that dead weight before it damages you.
/ In practice
Why pruning your list helps
It feels wrong to stop mailing people you worked to acquire, but unengaged subscribers actively work against you. Providers watch how recipients interact with your mail, and a large segment that never opens drags down the engagement signals your reputation depends on — which lowers inbox placement even for your engaged recipients. Continuing to mail the unengaged also raises your risk: abandoned addresses that turn into recycled spam traps will flag you the moment you hit them. Sunsetting removes both problems by concentrating your sending on people who actually want it.
How a sunset policy works
A typical policy defines an inactivity window — commonly three to six months with no engagement — after which a subscriber enters a sunset flow: usually a final re-engagement campaign asking whether they still want to hear from you, then suppression of those who don't respond. The thresholds depend on your sending frequency and audience, and the goal isn't to punish quiet subscribers but to stop pouring reputation risk into addresses that have gone cold. Done well, a sunset policy keeps your active list engaged and your complaint rate low.
/ Re-engagement and thresholds
The re-engagement step
A good sunset policy rarely drops subscribers silently; it gives them a chance to stay first. When a subscriber crosses the inactivity threshold, a re-engagement campaign — a short series asking whether they still want to hear from you, sometimes with an incentive — separates the genuinely lapsed from those who were simply quiet. Those who respond are kept; those who don't are suppressed. This step matters because some unengaged subscribers are still reachable, and a blunt policy that removes everyone inactive loses people who would have re-engaged if asked.
Setting the right window
The inactivity window depends on how often you send and what your mail is. A daily sender accumulates inactivity signals fast and might sunset after a few months of silence; a monthly newsletter needs a longer window before silence means disengagement. The metric you measure also matters — with open rate now unreliable thanks to privacy features, engagement is better judged on clicks and other real actions. The goal throughout is the same: keep your active list concentrated on people who want your mail, so the reputation signals that drive inbox placement stay strong.
/ Related terms
A smaller engaged list beats a big dead one. We help you prune it.
We set up sunset policies that retire cold subscribers before they hurt your reputation, keeping your active list engaged. Bring us your list and we'll design the flow.
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