Winback and Sunset Flows: A Retention Strategy

Short answer. Use a winback flow when a prior customer has passed the normal repurchase window but still has a plausible reason to return. Use a sunset flow after sustained inactivity across email, site, checkout, and purchase signals, when the next decision is whether to stop marketing sends. Winback seeks another purchase. Sunset protects list quality and sender reputation. Keep the two objectives, audiences, and success metrics separate.

“Inactive” can describe two different problems. A customer may not have purchased recently but still click emails and browse the site. A subscriber may have never purchased, visited, clicked, or opened intentionally. Treating both as one audience creates a sequence that is too promotional for list cleanup and too pessimistic for customer retention.

This guide defines the overall strategy. For platform steps, use the Klaviyo winback flow tutorial and the Klaviyo sunset flow tutorial.

The four-stage retention system

Suppression is an operational state, not an emotional judgment about the customer. The profile history can remain useful for service, analytics, or future consent decisions, subject to the organization's data-retention obligations.

Separate purchase inactivity from email inactivity

Build the strategy on two axes.

Purchase inactivity

Questions to answer:

• When do customers normally place the second order?
• How does that interval change by first product or category?
• Are there seasonal or replenishment effects?
• Does the customer have one order, several orders, or prior VIP value?
• Has the customer bought through another channel that is not reaching Klaviyo?

A customer who buys furniture every two years is not lapsed after 90 days. A customer who normally replenishes every 30 days may be at risk after 60. Use your observed order intervals instead of an industry table copied from another brand.

Marketing inactivity

Questions to answer:

• Can the profile currently receive the intended marketing channel?
• How many messages had a real opportunity to be seen?
• Has the profile clicked, visited, viewed a product, started checkout, or purchased?
• Are open events affected by Apple Mail Privacy Protection?
• Did the inactivity begin after a frequency, product, or service change?

Klaviyo records an Apple Privacy Open property because Mail Privacy Protection can preload the tracking pixel without human attention. An open with that flag does not prove engagement. Review Klaviyo's MPP documentation and give greater weight to clicks, purchases, and verified site activity.

Stage 1: prevent lapse before using a winback

Winback should not compensate for a weak customer experience. Before adding another discount, inspect the reasons customers may not return:

• the product has not delivered expected value;
• the customer does not know how to use or replenish it;
• fulfillment or support created friction;
• the next purchase recommendation is irrelevant;
• frequency is too high or messages are repetitive;
• the business has no natural repeat-purchase use case.

Prevention journeys

Use post-purchase education, replenishment, cross-sell, loyalty, and service messages when they match the product. A “surprise and delight” moment can also reinforce the relationship before lapse, but only when the value is real.

Examples include:

• an unexpected useful sample in a repeat order;
• early access for a verified loyal customer;
• proactive care instructions;
• a service recovery after a known issue;
• a personal thank-you or relevant content with no purchase requirement.

A coupon described as a surprise but conditioned on an immediate purchase is still a promotion. That may be effective, but name and measure it accurately.

Stage 2: define the winback audience

A winback audience starts with prior purchase behavior. It should not include every subscriber who stopped opening.

Minimum audience logic

Placed Order at least once over all time
AND
has passed the relevant repurchase window
AND
can receive the intended marketing channel
AND
has not already completed a recent winback attempt

The repurchase window can be implemented with a metric-triggered flow and delay, or with a carefully designed segment depending on the platform and use case. In Klaviyo, the official standard uses a Placed Order trigger, an initial delay slightly longer than the normal buying cycle, and a profile filter of Placed Order zero times since starting this flow.

Segment by relationship, not just recency

Use RFM customer segmentation when a simple order-count split is not enough.

Design the winback sequence around one hypothesis

Klaviyo currently recommends no more than three winback emails per recipient in its official winback guide. The exact content should answer why this customer might return.

Email 1: reopen relevance

• Acknowledge the gap without guilt.
• Show what has changed or what the customer may have missed.
• Use prior category context only when the data is reliable.
• Give one clear path back.

Email 2: add a reason to act

• Present useful products, education, or service.
• Introduce an incentive only when the economics support it.
• Give the offer a real expiration if urgency is used.
• Exclude customers who already purchased.

Email 3: close the attempt cleanly

• Restate the strongest reason to return.
• Make preferences and unsubscribe easy to find.
• Avoid repeated emotional pressure.
• Define what happens if the customer takes no action.

Test offer versus no offer, product set, cadence, or subject line one variable at a time. Do not call a change incremental unless the experiment includes a valid control or holdout.

Stage 3: define the sunset audience

Sunset begins when the evidence says normal marketing sends are unlikely to be useful. This is broader than “has not opened in 180 days.”

Klaviyo's March 2026 sunset flow documentation uses a strict multi-signal definition for its prebuilt Sunset (Email) segment. It looks for an older profile that can receive email marketing, has received multiple emails, and has no recorded open, click, site visit, product view, checkout start, or order activity.

That template identifies a never-engaged cohort. A business can also create a lapsed-engagement cohort using rolling windows, but it should protect:

• customers with recent or high-value purchases;
• seasonal customers whose natural cycle is long;
• profiles with site or checkout activity;
• people whose open data is distorted by MPP;
• data gaps from another store, POS, or prior ESP;
• recent subscribers who have not had enough message opportunities.

Sunset is not a disguised sale

The purpose is to obtain a final meaningful signal before stopping normal sends. One or two concise emails are often enough, with a third at most under Klaviyo's current recommendation.

A useful sunset message offers clear choices:

• continue receiving the relevant content;
• update preferences;
• unsubscribe;
• take no action and leave the active marketing audience after the stated period.

Avoid using a large coupon as the only definition of engagement. It can retain deal seekers without proving future interest in the email program.

Stage 4: make suppression a governed process

Klaviyo currently does not provide a native Suppress profile flow action. Its recommended process is:

1. Use flow filters so profiles who engage no longer qualify for the final step.
2. Add an Unengaged = true or equivalent profile property at the end.
3. Build a segment from that property.
4. Review sample profiles and the current member count.
5. Choose Suppress current members.
6. Repeat the operation as new profiles join, or implement an approved API process.

The bulk action is a snapshot. It does not automatically suppress future members of the segment.

Suppress, unsubscribe, and delete are different

Manual suppression does not necessarily change the stored consent status. Klaviyo also documents that a resubscription or manual unsuppression can make a profile reachable again under specific conditions. Do not describe suppression as permanent deletion.

Review the current active profile management guide before writing internal policy.

Progressive versus direct sunset policies

Progressive policy

Use a progressive approach when the base contains customers with varied purchase cycles or when data completeness is uncertain.

1. Narrow regular campaigns to the engaged audience.
2. Keep high-intent flows protected by consent and their own logic.
3. Move lapsed customers through winback.
4. Move sustained non-responders through sunset.
5. Review and suppress the final inactive group.

This approach creates more checkpoints and makes false positives easier to catch.

Direct policy

A direct bulk-suppression project can make sense for an obviously polluted cohort such as old, never-engaged profiles with no purchase or site activity. Run sample QA first. Confirm source history, consent migration, order sync, and suppression scope. The apparent simplicity of a one-time cleanup does not remove data risk.

Connect the two flows without conflating them

The handoff should be explicit:

Customer passes expected repurchase interval
  -> winback attempt
  -> purchases: return to active customer lifecycle
  -> clicks or visits but does not buy: retain or nurture based on policy
  -> no meaningful activity: evaluate for sunset segment
  -> completes sunset without activity: review and suppress

A click without purchase is a useful sign for list eligibility, but it is not a successful customer winback. A purchase is a winback conversion. Keep those metrics separate.

Measure the strategy without invented benchmarks

Winback metrics

• Eligible entrants.
• Purchasers during the defined measurement window.
• Revenue per recipient and gross margin after incentives.
• Time to next purchase.
• Unsubscribes and complaints by message.
• Incremental conversion versus a holdout, when available.

Sunset metrics

• Profiles entering the sunset cohort.
• Profiles producing a verified click, site action, checkout, or purchase.
• Profiles tagged for suppression.
• Profiles actually suppressed after review.
• Complaint, bounce, and engagement trends for the remaining audience.
• Active-profile count and billing impact.

An increase in open rate after suppression can be partly mechanical because inactive recipients left the denominator. Do not present that change alone as proof of improved inbox placement. Use mailbox-provider data, complaint signals, bounce behavior, and controlled delivery testing where available. The email deliverability guide explains the difference between delivery, engagement, and inbox placement.

Governance checklist

• The normal repurchase interval is documented by category.
• Winback and sunset have separate entry criteria and owners.
• Marketing eligibility is checked for every channel.
• Purchasers exit future winback promotional steps.
• Apple Privacy Opens are not treated as verified human engagement.
• Seasonal and recent customers are protected from premature sunset.
• Suppression requires a sample review and an accountable role.
• Transactional message ownership remains separate from marketing suppression.
• Data retention and deletion rules are reviewed with qualified counsel.
• Every threshold has a review date and business rationale.

FAQ

What is the difference between a winback flow and a sunset flow?

A winback flow targets prior customers and seeks another purchase after the normal buying cycle. A sunset flow targets profiles with sustained inactivity and gives them a final chance to show interest before the business stops ordinary marketing sends. Winback is a retention motion. Sunset is list-hygiene and deliverability governance.

How long should I wait before starting winback?

Wait slightly longer than the normal buying cycle for the relevant product or customer group. Calculate the interval from your order history. A fixed 90-day trigger can be too late for replenishable goods and far too early for furniture, electronics, or other long-cycle categories.

Should a click remove someone from sunset?

Usually, a verified click is a meaningful engagement signal and should prevent immediate suppression. Decide how long that protection lasts and whether the destination confirms the subscriber's intent. An Apple Privacy Open alone should not have the same weight.

Does suppression permanently delete a Klaviyo profile?

No. Suppression makes the profile ineligible for marketing email and excludes it from active-profile billing, but the profile and its history remain. Deletion is a separate, permanent data action. Klaviyo also documents paths for resubscription or manual unsuppression.

Can winback and sunset use SMS?

Only for profiles eligible for SMS under the applicable consent, registration, and jurisdictional rules. Email eligibility does not create SMS permission. Coordinate pressure across channels and give the SMS a distinct purpose rather than duplicating the email.

Build a retention exit policy before you need it

Winback and sunset work when the team agrees on who is still commercially recoverable, what counts as meaningful engagement, and when ordinary marketing should stop. Deliver can map the cohorts, design the flow handoff, validate Klaviyo data, and document the suppression process.

Review your winback and sunset strategy with Deliver.

Continue with:

• Implement a Klaviyo winback flow
• Implement a Klaviyo sunset flow
• Build an ecommerce retention strategy

Charlotte Rodrigues, CRM Lead at Deliver. Updated July 16, 2026.