How to Run a Re-Engagement Email Campaign That Protects Inbox Placement

A re-engagement campaign is a short series, usually two or three emails, sent to subscribers who have stopped interacting, asking them to confirm they still want your mail. Verify the segment first, make staying one click, count only clicks and other real actions as a yes, and suppress everyone who does not answer. The goal is a smaller list that wants your mail, not a temporary bump in opens.

When to call someone inactive, and the policy around it, is covered in how to write a sunset policy. This post is about running the campaign itself.

Who goes into the campaign

Include people who were once real, engaged subscribers and have gone quiet; leave out anyone you never had a working relationship with. A re-engagement series is for lapsed readers, not for rescuing a bad list.

Group	Include?
Opted in, clicked or bought in the past, nothing for 6+ months	Yes. This is the core segment
Signed up but never clicked anything	Yes, but send to them last
Already unsubscribed	Never
Hard bounced before	Never. They are suppressed for a reason
Imported from a source with no record of consent	No. A re-engagement email is still unsolicited mail to them
Engaged in the last 90 days	No. They do not need it, and it would read oddly

Use clicks, replies, purchases and logins to decide who is inactive. Apple's Mail Privacy Protection "downloads remote content in the background by default — regardless of whether you engage with the email", so open data will make some silent subscribers look active and keep them out of the campaign.

Verify the segment before the first send

An inactive segment is where dead mailboxes collect, so check it before you mail it. Run it through a verifier, drop anything that comes back invalid, and hold risky addresses such as catch-alls for the final batch. The full reasoning is in the sunset policy guide, so we will not repeat it, but the order matters: the bounces from an unverified win-back send land on the same campaign that is already your most complaint-prone. If you have not checked these addresses recently, the free email checker is enough for a spot check, and a bulk verifier for the whole segment.

The message: one question, two buttons

The first email should ask one thing, whether they want to keep hearing from you, and make both answers a single click. Everything else in it is optional.

A structure that works:

1. Who you are, in the first line. After months of silence, people do not always recognise the sender name.
2. Why they are getting this: they subscribed, and you have not seen them in a while.
3. One button to stay, which records a click you can act on.
4. One link to leave, equally visible. Making it hard to find invites the spam button instead.
5. Optionally, a lighter option: fewer emails, or one topic only.

Keep the design plain. Heavy promotional layouts read as yet another marketing email, which is the thing the reader has been ignoring.

If you send in bulk, the campaign still needs one-click unsubscribe. Gmail's sender guidelines require that marketing messages from senders of 5,000 or more messages a day "support one-click unsubscribe, and include a clearly visible unsubscribe link in the message body." Implementation details are in our guide to one-click unsubscribe.

Subject lines

Say plainly what the email is. Clever or misleading subjects, such as a fake "Re:" or an invented order notice, are a fast route to complaints from exactly the people least invested in you. Approaches that stay honest:

• The direct question: "Do you still want emails from [Brand]?"
• The notice: "We'll stop emailing you unless you tell us otherwise"
• The choice: "Fewer emails, or none? Your call"
• The value reminder, if you have something real: "Here's what you missed this year"

Which works best for your audience is something to test on your own list. We are not quoting win-back rates from other companies, because they depend on the list, the brand and how inactive was defined.

Offer a downgrade, not just stay-or-go

A preference option keeps people who like you but get too much mail. Many lapsed subscribers did not lose interest in the brand; they lost interest in the frequency. Offering a monthly digest or a single topic gives them a third answer between staying as-is and leaving.

Keep it simple. In the US, the FTC's CAN-SPAM compliance guide says you cannot make a recipient take any step other than replying or "visiting a single page on an Internet website" to opt out. A preference page is fine, as long as leaving everything is an option on that same page and does not require logging in or answering questions.

Sending it without damaging your reputation

Send in batches, best-scoring contacts first, and watch complaints after each one. This segment is the most likely part of your list to press "report spam", and both large mailbox providers publish limits:

• Gmail asks bulk senders to keep the spam rate in Postmaster Tools below 0.10% and to "avoid ever reaching a spam rate of 0.30% or higher". Its FAQ says senders above 0.3% are ineligible for mitigation until they have stayed below it for 7 consecutive days.
• Yahoo's sender best practices ask senders to keep the spam rate below 0.3% and to honour unsubscribes within 2 days.

Practical rules for the send:

1. Start with the most recently active part of the segment, for example people inactive for six to nine months, before those inactive for two years.
2. Leave a day or two between batches so complaint data has time to appear in Google Postmaster Tools or your ESP's reports.
3. Stop if complaints rise on a batch. The remaining batches are older and will be worse, not better.
4. Process every unsubscribe promptly. Google recommends fulfilling unsubscribe requests within 48 hours; CAN-SPAM's legal limit is 10 business days. The tighter number is the one to plan for.

Measuring the result

Count a subscriber as re-engaged only when they did something MPP cannot fake. That means:

• Clicked the stay button, or any link
• Changed their preferences
• Replied
• Bought, logged in or used the product

An open on its own does not count. Neither does a delivered message with no further action.

Report three numbers per batch: how many re-engaged, how many unsubscribed, and how many complained. Unsubscribes are a good outcome here. Someone who leaves through the link is someone who did not press "report spam", and the list is better for losing them.

What to do with people who never answer

Suppress non-responders after the final email; do not keep mailing them on the hope that the next campaign lands. Gmail's own guidance is to "consider unsubscribing recipients who don't open or read your messages", and Yahoo recommends periodically sending "a reconfirmation email to inactive subscribers". A re-engagement campaign is that reconfirmation. Silence is the answer.

Suppress rather than delete, so a CRM sync, a form resubmission or a future import cannot quietly put them back. If someone later signs up again through your own form, they come back as a new subscriber with fresh consent.

Long-dead addresses on a list are also one of the routes by which spam traps get in: a mailbox abandoned for years can be repurposed by a provider to catch senders who never clean their lists. Suppressing non-responders closes that route.

A simple timeline

Day	Action
−3	Build the segment from clicks and purchases, not opens. Verify it; remove invalid
0	Email 1 to the first batch: "Do you still want these emails?"
2 to 6	Further batches, if complaints on earlier ones stayed low
7	Email 2 to non-responders: short reminder, same two buttons
14	Optional final notice: "This is the last email unless you click"
21	Suppress everyone who did not act. Move responders back to the main list

Run it once or twice a year, as your sunset policy defines. A list that goes through this regularly is smaller than the one you started with, and it is the version of your list that mailbox providers will keep delivering to the inbox.