Keeping every old address enlarges the list without necessarily enlarging the audience. A retirement policy identifies inactivity, offers a reasonable chance to reconnect and stops sending when interest is no longer evident.
Define inactivity using several signals
Use clicks, site activity and conversions where an appropriate basis exists, since opens are imperfect. Match the observation window to sending frequency.
Separate new and established subscribers
A new subscriber who never engaged needs a different message from a formerly loyal reader who drifted away. Do not use one automation for both.
Run limited re-engagement
Remind readers of the value, offer frequency choices and request a clear action. Avoid endless sequences that worsen the problem.
Stop marketing sends
After the threshold, suppress the address rather than continuing because nobody unsubscribed. Retain only necessary data and handle transactional needs separately.
Measure list quality
Monitor complaints, bounces, active readers and conversions by cohort. A smaller active list may be a much stronger asset.
This framework is an original DigitalNow editorial methodology.