Re-engaging dormant contacts

Contacts who have not engaged in a long time are the quiet deliverability risk. The send preflight flags them — "Some of these contacts haven't heard from you in a while" — because they are the group likeliest to complain.

Why they cost you

Mailbox providers judge you on engagement. A large dormant segment drags down that signal, which affects delivery to the people who do want your email.

And when a forgotten subscriber finally notices you, "report spam" is a more likely response than "unsubscribe" — at a 0.08% tolerance, a handful is enough to stop a campaign. See Spam complaints.

Do not define dormant by opens alone

Open tracking is unreliable in both directions. "Has not opened in six months" sweeps up people who read every email in a client that blocks images. See Why open rates are unreliable.

Use clicks over a long window, or a purchase, and be generous with the window.

A re-engagement send, done carefully

• Keep it small. A slice, not the whole dormant list at once. If complaints spike you want to have learned it on 500 people rather than 50,000.
• Be direct. "Still want to hear from us?" is more honest, and works better, than a discount pretending nothing happened.
• Make unsubscribing easy. The goal is a clean answer either way — an unsubscribe here is a good outcome.
• Send it separately from your normal campaigns, so the results are readable and one bad response does not colour a healthy send.

Then act on the silence

The part people skip. If someone ignores the re-engagement email too, stop sending to them.

That feels like throwing away a contact. It is not: they were already not reading, and they were costing you delivery to everyone else. A smaller engaged list out-performs a larger indifferent one on every measure.

Next: build an Engaged segment first — see Segments worth building first — and send your next campaign to that.