Email list hygiene - how to audit and sunset it (with or without AI)

What good email list hygiene checks for

List hygiene is really about finding who has stopped engaging and deciding whether to win them back or cut them.

1. 1.

   Unengaged 90+ day subscribers - No open or click in 90+ days signals decay and hurts sender reputation

2. 2.

   Never-opened subscribers - People who never engaged since signup rarely convert and inflate list size

3. 3.

   Engagement decay trend - Rising unengaged counts month over month warns of deliverability risk ahead

4. 4.

   Bounced or invalid addresses - Hard bounces should be suppressed immediately to protect sender score

5. 5.

   Purchasers vs non-purchasers overlap - Unengaged buyers deserve different treatment than unengaged non-buyers

6. 6.

   Sunset or re-permission candidates - Segment ready for a final win-back attempt before removal from sends

Takeaway: Run this scan monthly so decay is caught early and your sender reputation stays healthy.