What is a sunset flow?
A sunset flow is an automated email sequence that gives your long-dormant subscribers one final chance to re-engage, then suppresses anyone who still does not open or click. It is the cleanup mechanism of your email programme. Rather than emailing people who stopped paying attention months ago, the sunset flow asks them, plainly, whether they still want to hear from you, and quietly removes those who say nothing. The point is not to shrink your list for its own sake. It is to protect your ability to reach the inbox of everyone who does want your emails.
This guide is the final flow in our wider breakdown of the eight ecommerce email marketing flows every Shopify and WooCommerce brand should run. Where the other seven flows are built to drive revenue, the sunset flow protects it, by keeping your sender reputation healthy so your abandoned cart, welcome and VIP emails actually land. Below we cover how to define an unengaged subscriber, how the sunset flow differs from a win-back, the exact structure to build, and how to set it up in Klaviyo and on WooCommerce.
Why unengaged subscribers quietly damage your deliverability
Mailbox providers such as Gmail and Apple decide where your emails go, the inbox or the spam folder, largely based on how people engage with them. When a big slice of your list never opens or clicks, your engagement rates fall, and those providers read that as a signal that your emails are unwanted. Over time, even your best, most engaged subscribers start seeing your emails land in spam.
So the cost of a bloated list is not just the monthly platform fee for contacts who never buy. The real cost is paid in deliverability. Every send to people who ignore you drags down the inbox placement of the people who do not. A sunset flow is how you stop that slow decline before it reaches the customers who matter.
How to define an unengaged subscriber
The flow is only as good as the segment that triggers it, and most brands define unengaged too loosely or too aggressively. Two principles keep you on the right side of it.
Judge email engagement, not site activity, for deliverability
A common default mixes website browsing into the unengaged definition, sparing anyone who visited the site recently. But site behaviour has no bearing on how mailbox providers judge you; only email opens and clicks do. If someone has not opened or clicked in months, they are hurting your deliverability whether or not they browsed last week. For the suppression decision, base unengagement strictly on email engagement.
Give subscribers a fair number of emails before labelling them
Do not sunset someone after a thin window. A subscriber needs to have received a reasonable volume of emails, often in the region of fifteen to twenty, with no opens or clicks, before you can fairly call them unengaged. The right time window depends on your sending frequency: a brand mailing weekly reaches that volume far faster than one mailing monthly. A six-month inactivity window is a common, sensible baseline for regular senders.
Separate buyers from never-buyers
Someone who has bought from you before is worth more effort than someone who never has. Split your dormant subscribers: past purchasers deserve a proper win-back attempt first, while subscribers who never opened or bought can go more directly into the sunset and suppression path.
Not sure if your sunset segment is set up right?
A loose definition shrinks your list too fast; a loose one keeps you emailing ghosts. We audit and build retention flows for Shopify and WooCommerce brands. Talk to our email team.
Sunset flow vs win-back flow: which to send
These two flows are often confused, but they do different jobs and run at different points in the lifecycle.
- Win-back flow. Aims to recover a lapsed customer with a relevant offer or reminder. It is a revenue play, usually aimed at people who have bought before and gone quiet. We cover it in detail in its own post within the flows cluster.
- Sunset flow. Aims to clean the list. It is a deliverability play, the last contact before you suppress someone who has not engaged at all.
In practice they run in sequence for past buyers: attempt the win-back first, and if that fails, the sunset flow delivers the final goodbye before suppression. For subscribers who never engaged or never purchased, you can skip straight to the sunset flow.
The sunset flow structure that works
Keep it short. One to three emails is the standard, because repeatedly contacting unengaged people is exactly what you are trying to stop. A reliable structure:
- Re-engagement email (the honest ask). A plain-text, personal email that asks directly whether they still want to hear from you. Use their first name, write from a real person, and keep the manage-preferences and unsubscribe links prominent. Mention anything new since they went quiet.
- Final reminder with an incentive (optional). A short follow-up a few days later. For past buyers, a meaningful offer can earn a last click. For never-buyers, a simple confirm-you-want-to-stay message is enough.
- The goodbye email. A brief, friendly note that this is the last email unless they act, with a clear way to stay subscribed. Add a short grace period after it for any final opens or clicks.
Crucially, add a flow filter that removes anyone who opens or clicks at any point. The moment a subscriber re-engages, they should drop out of the sunset flow and rejoin your active list. The flow should also be plain text and as personal as you can make it, since a stripped-back email often cuts through where another polished campaign would not.
Setting up the sunset flow in Klaviyo
On Shopify, Klaviyo reads your engagement and order data natively, which makes the sunset flow straightforward to build:
- Build the unengaged segment. Define it on email engagement: received a meaningful number of emails, with no opens or clicks across your chosen window (commonly six months for regular senders).
- Trigger on segment entry. Start a flow when a profile is added to the unengaged segment. Segment-triggered flows fire once per profile.
- Add the engagement exit filter. Set a flow filter so anyone who opens or clicks since entering the flow is removed automatically and never tagged for suppression.
- Tag and exit. Anyone who completes the flow without engaging is the cohort you will suppress next.
Where it fits, a single well-timed SMS or a low-cost retargeting ad to the at-risk segment can reach a dormant subscriber in a different environment before the final goodbye. For how this sits alongside your other channels, see our complete guide to ecommerce marketing in 2026.
Running a sunset flow on WooCommerce
Most agencies build for Shopify and leave WooCommerce founders to work it out alone. Every part of the sunset flow works on WooCommerce; the tooling differs because WooCommerce does not pass engagement and order data to your email platform on its own. You need a connector:
- Klaviyo for WooCommerce. The official integration syncs orders and email engagement, so you can build the unengaged segment on opens and clicks exactly as on Shopify.
- Omnisend. A solid email-and-SMS option for smaller stores, with native WooCommerce support and built-in sunset-style automation.
- MailPoet. A WordPress-native choice that keeps sending and engagement data inside your site, suitable for leaner setups.
Once the connector reliably tracks email engagement, the segment logic, the engagement exit filter and the email structure are the same as the Klaviyo setup above. The principle holds on both platforms: define unengaged on email behaviour, give one to three final emails, and let anyone who re-engages drop out.
What to do after the flow: suppress, do not delete blindly
When the flow ends, you suppress the subscribers who never engaged. Suppression keeps the profile in your platform but stops future marketing sends reaching them, which protects deliverability while preserving the record. This is usually safer than hard-deleting, which loses the history and any chance of a future, consent-based reactivation.
Note that suppression applies to the people in the segment at that moment, so you repeat the process periodically as new subscribers go quiet. List hygiene is a habit, not a one-off. For very long-dormant contacts who never opened anything, deletion can be appropriate, but make it a deliberate decision, not the default.
Common sunset flow mistakes to avoid
- Mixing site activity into the unengaged definition. Only email opens and clicks affect deliverability. Judge unengagement on email behaviour.
- Sunsetting too aggressively. Labelling someone unengaged after too few emails churns recoverable subscribers and shrinks your list needlessly.
- Sending too many emails. More than three messages to people who are already ignoring you does more harm than good.
- Forgetting the engagement exit filter. Without it, you risk suppressing someone who re-engaged mid-flow.
- Treating it as a one-off. Suppression only covers current members, so the flow and the suppression step need to run on an ongoing cadence.
Frequently asked questions
A sunset flow is an automated email sequence that gives dormant subscribers one final chance to re-engage, then suppresses anyone who still does not open or click. Its purpose is deliverability: removing unengaged contacts so your emails keep reaching the people who do want them.
When they have received a fair volume of emails, often fifteen to twenty, with no opens or clicks, commonly across a six-month window for regular senders. Base the definition on email engagement, not website activity, since only opens and clicks affect deliverability.
A win-back flow tries to recover a lapsed customer with an offer; it is a revenue play. A sunset flow cleans the list; it is a deliverability play and the last contact before suppression. For past buyers, run the win-back first and the sunset flow only if that fails.
One to three. Repeatedly contacting people who already ignore you damages deliverability, which is the opposite of the goal. Keep it short, plain text and personal, and add a filter that removes anyone who opens or clicks.
Usually suppress. Suppression stops future marketing sends while keeping the profile and its history, which protects deliverability and leaves room for future consent-based reactivation. Reserve deletion for very long-dormant contacts who never engaged at all.
Yes. WooCommerce needs a connector such as Klaviyo for WooCommerce, Omnisend or MailPoet to track email engagement. Once that is in place, the segment logic, exit filter and email structure are the same as on Shopify.
Protect the revenue your other flows generate.
The sunset flow keeps your sender reputation healthy so every other email lands. We build the full eight-flow stack for Shopify and WooCommerce brands scaling across the UK, US, Europe and MENA. Book a call with Engage Positive.
