Sunset Policy
The systematic process of removing unengaged subscribers from your email list to maintain deliverability and improve campaign performance.
Definition
A sunset policy defines when and how inactive subscribers are removed from active email lists. Typically, subscribers who haven't opened or clicked in 90-180 days enter a re-engagement sequence before suppression.
This counterintuitive practice of shrinking your list actually improves overall performance and deliverability.
Why It Matters
Inactive subscribers hurt deliverability—ISPs interpret low engagement as a spam signal. Continuing to email unengaged contacts damages your reputation and wastes resources.
A smaller, engaged list outperforms a large unengaged one every time.
Examples in Practice
An e-commerce brand sunsets 45,000 subscribers who haven't engaged in 180 days after a failed re-engagement campaign. Their open rate jumps from 18% to 32%, and revenue per email increases 28%.
A B2B company implements a 120-day sunset with a 3-email win-back sequence. They recover 8% of at-risk subscribers while removing 22% who confirmed disinterest.