Suppress the subscribers who quietly cost you the inbox.
Every list carries people who stopped opening long ago, and mailing them steadily erodes your inbox placement for everyone else. A sunset flow gives those subscribers a genuine last chance, then quietly suppresses the ones who stay silent. It is not a revenue flow. It protects the deliverability that every one of your revenue flows depends on.
List hygiene, not a sales flow
A sunset flow targets chronically unengaged subscribers, the people who have not opened or clicked in months, gives them one clear chance to stay, and suppresses the ones who do not take it. Unlike every other core flow, its job is not to sell. It is to protect the thing that makes selling possible: your ability to reach the inbox. Mailboxes decide where your email lands partly on how your audience engages, so a big block of people who never open is a steady drag on placement for your whole program. Removing them is uncomfortable, because the list gets smaller, but a smaller engaged list out-earns a large ignored one. You build the flow by defining the unengaged as a segment, giving them a genuine last chance, and suppressing the ones who stay silent.
Why pruning the list makes the rest of your email worth more
It feels backward to email fewer people on purpose, so it helps to see the mechanism. Inbox providers watch engagement signals to decide whether your mail belongs in the inbox or the spam folder. A large, unengaged segment sends the wrong signal on every send, which lowers placement for the campaigns and flows that actually make money. Suppress that segment and the signal flips: your sends now go mostly to people who open, placement improves, and the same campaign quietly earns more because more of it lands. That is why the sunset flow pairs naturally with a wider deliverability discipline, and why it is worth running even though the flow itself earns almost nothing.
A sunset flow that works
One or two emails offering a real last chance, then the step that actually matters: suppression.
The honest last chance
When they cross the unengaged threshold
A plain, direct email: we have noticed you have not opened in a while, do you still want to hear from us? Make staying a single click (a button or a preference link) and keep it short. No heavy discount; you are confirming interest, not buying it back.
One final reminder
A few days later, if still silent
A short nudge that this is the last email unless they act. Some stores add a small incentive here, but only if the subscriber was ever a customer; for never-engaged sign-ups, do not spend margin on a list you are about to prune.
Quietly remove the dead weight
After the last chance goes unanswered
Anyone who still has not engaged is suppressed, not deleted. They stop receiving sends, your engaged-only audience gets cleaner, and your sending reputation stops carrying people who never open. This is the whole point of the flow.
The rules that keep it working
A sunset flow only helps if it actually removes people, so the guardrails are about doing it deliberately.
Define unengaged for your send frequency
There is no universal number. Base the threshold on no opens or clicks across a window that fits how often you send, so a high-frequency sender sunsets sooner than a brand that emails monthly. In practice that is a segment along the lines of no open or click in the last 90 to 120 days and no recent purchase. Tie it to engagement, not to time alone.
Give a genuine last chance, then act
The re-engagement email only works if you actually suppress the non-responders. One setup detail quietly breaks it: turn Smart Sending off on the sunset emails, or Klaviyo may skip the very people you are trying to reach because they were mailed recently. A sunset flow that asks are you still there and then keeps mailing everyone anyway does nothing for deliverability. The suppress step is the flow.
Suppress, and exclude recent buyers
Suppress rather than delete, and make sure anyone who recently purchased or engaged is filtered out, so you never sunset a customer who is quietly reading but not clicking. Engagement plus recency together decide who really belongs here.
Watch the deliverability payoff
The signal that a sunset flow is working is not its own revenue. It is your open rates, spam-complaint rate, and inbox placement improving across everything else you send once the unengaged are out of the mix.
The value shows up everywhere except this flow
Judged on its own revenue, a sunset flow looks like the weakest one you run, and by design it is: the people in it had already stopped engaging, so it earns almost nothing per recipient. Its real return shows up in every other send. Better inbox placement lifts the open and click rates, and therefore the revenue, of your campaigns and your high-value flows like win-back and the rest of the core set. That makes it hard to value in isolation, which is exactly the kind of thing a full-program view is for. A free Klaviyo audit flags whether an unengaged segment is dragging your deliverability and what cleaning it up is worth across everything else you send.
Is it safe to connect Klaviyo?
- Read-only. It can read your campaign and flow performance. It cannot send, edit, or delete anything in your account.
- No customer data stored. It works from your metrics, not your subscriber list. Names, emails, and phone numbers are never stored.
- Nothing ships without you. Built emails land as drafts for your review; nothing is pushed to Klaviyo on its own.
- Built by an operator. David Refaeli-Berman ran enterprise email at Chewy, Amazon, Overstock, and Bed Bath & Beyond.
Questions
What is a sunset flow in Klaviyo?
It is an automated flow that targets chronically unengaged subscribers, people who have not opened or clicked in a long time, gives them a clear last chance to stay, and then suppresses the ones who do not respond. Its job is list hygiene, not sales. By quietly removing the dead weight, it keeps your sending reputation healthy so the rest of your emails keep reaching the inbox.
When should a subscriber enter a sunset flow?
When they have gone quiet on engagement for long enough that mailing them is more likely to hurt than help. A common trigger is no open or click across a window of roughly three to six months, adjusted for how often you send: a daily sender reaches that threshold faster than a monthly one. The point is to catch people who have effectively stopped paying attention before their non-engagement drags on your deliverability.
Should a sunset flow delete or just suppress contacts?
Suppress, do not delete. Suppressing stops you from mailing them while keeping the record, so you do not lose the history and you do not risk re-importing them later and starting the damage over. Deleting throws away data you may want and offers no extra benefit. The goal is simply to stop sending to people who are not engaging.
Does a sunset flow lose revenue?
Almost none directly, and that is the point. A sunset flow earns very little per recipient because the people in it had already stopped engaging. What it protects is far more valuable: your inbox placement. Chronically mailing the unengaged is one of the fastest ways to land in spam, which quietly taxes every campaign and every revenue-driving flow you send. Sunsetting is profitable indirectly, through deliverability.
What is the difference between a sunset flow and a win-back flow?
A win-back flow targets lapsed customers by purchase behavior and tries to earn another order; it is about revenue. A sunset flow targets unengaged subscribers by open and click behavior and, if they stay silent, suppresses them; it is about list hygiene. They work together: many stores run a win-back first, and let the contacts who never re-engage fall through to a sunset.
Find out what your unengaged subscribers are costing you.
A free audit checks whether a dead-weight segment is dragging your inbox placement, and what suppressing it is worth across every email you send.
Check my list health free