Continuing to mail unengaged contacts teaches providers your mail is unwanted. Sunsetting protects the rest of the list.
The metrics that matter#
- Authentication pass rate: share of mail passing SPF, DKIM, and DMARC alignment. Healthy: 99% or higher.
- Spam complaint rate: Gmail enforces at 0.3%; stay under 0.1%.
- Hard bounce rate: under 2%; above 5% triggers platform reviews.
- Inbox placement: above 90% across major providers via seed tests.
- Engagement: click and reply rates by segment; opens are unreliable after Mail Privacy Protection.
Where to read them#
- Google Postmaster Tools for Gmail domain reputation, spam rate, and authentication.
- Microsoft SNDS and JMRP for Outlook.com IP reputation and complaints.
- Your ESP's delivery and bounce reports.
- DMARC aggregate reports for authentication by source.
Improving the numbers#
- Define inactivity: no clicks or replies in 90 days is a common threshold.
- Send a 2 to 3 message win-back series with a clear ask to stay subscribed.
- Suppress anyone who does not engage after the series.
- Keep a record of suppressed contacts for compliance and future opt-in.
Frequently asked questions#
Will sunsetting hurt my revenue?
Rarely. Inactive contacts produce little revenue, and improved placement for engaged contacts usually offsets any loss.