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Published October 22, 2026.
Measure engagement over a defined window
Choose an engagement window, such as 90 or 180 days, and define what counts as engaged: an open, a click, or a reply. Record the definition. Opens are less reliable after privacy changes, so pair them with clicks where possible.
Do not suppress a subscriber on a single missed open. A short window creates false negatives and shrinks the list faster than the business can replace it.
Separate bounces, complaints, and inactivity
Hard bounces are removed promptly. Complaints are suppressed and reviewed. Inactive subscribers enter a re-engagement path rather than being deleted immediately. Each group has a different cause and a different action.
Record the source of each suppression. "Removed for inactivity" without the window and the last engagement date is not an auditable record.
Use a re-engagement sequence with a clear end
Send a small number of messages that ask whether the subscriber still wants to hear from the team. If there is no response, suppress or delete according to the policy. Do not keep sending to an unresponsive list to protect a vanity metric.
Check consent records before re-engaging. A subscriber who opted out of marketing cannot be re-added through a re-engagement campaign.
Review the list monthly
Track list size, engaged share, complaint rate, and the number of addresses suppressed. A sudden change in complaints or bounces may point to a source-quality problem or a sending change.
Keep the review notes with the campaign calendar so the team can connect a list change to a deliverability event.
Related reading
For the supporting routine, see this guide and this guide. To discuss the workflow, contact us.
