From Send-All to Smart: A Klaviyo Guide to Engagement Segments and Sunset Flows

If you rely on email to drive sales, deliverability is the invisible lever that determines whether your messages make money—or quietly miss the inbox. The good news: you don’t need a complicated tech stack to get results. With a few clear segments, one well-structured sunset flow, and a simple churn-risk play, you can lift open rates, protect sender reputation, and recover slipping customers using only Klaviyo.

This guide is written for ecommerce teams of any size. If you’re new to email, you’ll get a step-by-step plan. If you’re experienced, you’ll find practical segment definitions and testing ideas you can apply today.

What “deliverability” actually means (in plain English) 

Deliverability is the likelihood that your email lands in the inbox (not the spam folder) and gets seen. It’s influenced by how people interact with your messages (opens, clicks, spam complaints), the health of your list (bounces, invalids, inactivity), and your technical setup (sending domain and authentication). You don’t need to be an engineer to improve it. The most effective lever is sending only to people who act like they want your emails—and giving the rest a graceful way to opt out or take a break.

Signs you need a tune-up

• Falling open rates over the last 30–60 days

• Spam complaints creeping above 0.1% of sends

• High hard bounce rate or many “suspended/inbox full” profiles

• Big campaign volume sent to everyone, every time

• A growing share of revenue from discounts to re-engage lapsed buyers

If any of these sound familiar, start with segmentation.

Step 1: Build engagement segments in Klaviyo

Your goal is to send more to people who show recent interest, less to those who don’t, and nothing to those who are clearly inactive. Create three tiers you’ll use across every campaign and flow.

1. Active Engagers (last 30 days)
   Logic example (adjust to your data):

• Has received email and is not suppressed

• Opened or clicked any email in the last 30 days

• OR purchased in the last 60 days

Why it matters: This audience keeps your inbox placement strong. It’s your control group for performance benchmarks.

2. Warming/At-Risk (31–90 days)
   Logic example:

• Subscribed to email marketing

• No open or click in 31–90 days

• Optional “intent” signals: visited site, viewed product, started checkout in last 30 days

Why it matters: These people haven’t engaged recently but are not lost. Treat them gently with lower frequency and value-forward content.

3. Dormant (90+ days)
   Logic example:

• Subscribed, but no opens or clicks in 90+ days

• No purchase in 180+ days

Why it matters: Continuously emailing this segment harms reputation. Use them only for a re-permission sunset flow (explained below); otherwise exclude from campaigns.

Pro tip: Build these segments once and reference them everywhere—campaign send filters, flow splits, and deliverability dashboards. If you run SMS, mirror the recency windows there too.

Step 2: Adjust your sending strategy with those segments

Once you have the three tiers, change how you send:

• Frequency: Send all major campaigns to Active Engagers. Send selected, high-value campaigns to At-Risk at half the frequency. Exclude Dormant from regular campaigns.

• Cadence testing: If you send three campaigns per week to Active, test one per week to At-Risk. Watch opens, clicks, and spam rate by segment.

• Domain considerations: If you have a lot of Gmail or Yahoo recipients, be extra conservative with At-Risk during big sales pushes.

• Content: Lead with value for At-Risk—education, social proof, product guides—before promotions. For Active, you can be more promotional without harming reputation.

Step 3: Launch a sunset (re-permission) flow

A sunset flow is an automated sequence that asks clearly: “Do you still want to hear from us?” If the answer is silence, you stop emailing. That discipline protects your list and your sender reputation.

Trigger

• When someone enters the Dormant (90+ days) segment

Branch 1: They open or click

• Email 1 (Day 0): Friendly check-in. Remind them what they signed up for and what they’ll miss. Provide a clear continue button and a preferences link.

• If they click, move them to At-Risk or Active (based on action) and resume regular messaging.

Branch 2: They don’t engage

• Email 2 (Day 3–5): Short, plain-language email. “We’ll pause emails unless you click to stay.” Offer a single CTA to continue.

• Email 3 (Day 7–10): Confirmation of pause. Let them know they can come back anytime.

Operational step

• If there’s no engagement after the sequence, stop emailing. In Klaviyo, you can manage this by relying on your Dormant segment to exclude people from all campaigns and flows. For stricter control, mark a profile property like do_not_email_due_to_inactivity = true and exclude it everywhere. If someone unsubscribes at any point, they’re automatically suppressed—no need for manual work.

Tone and design

• Plain text or very light templates often work best. Make the “stay subscribed” action unmistakable.

Step 4: Put a churn-risk save in place

When a customer is slipping away, you want to keep them without over-discounting or hurting deliverability. You can do this with either predictive traits (if available in your account) or simple proxies.

Segment logic options

Option A: Predictive

• “Likely to churn” is true

• AND not in Active Engagers (last 30 days)

Option B: Proxy (works for any account)

• No purchase in 120–180 days

• AND no email engagement in 31–90 days

• AND browsed recently (site visit or product view in last 30 days)

Flow outline

• Message 1: Helpful content that reduces friction (fit guide, how-to, top-rated picks, or customer stories). The CTA should be about value, not price.

• Message 2 (3–5 days later if no activity): Small, targeted incentive or perk for high-CLV customers (free shipping, free sample, points bonus). For low-CLV customers, continue with content or a low-cost perk to avoid margin erosion.

• Exit conditions: If they click or buy, route them back to Active. If they remain silent and slide into Dormant, your sunset flow will handle the rest.

Step 5: Clean your list and keep it clean

Even great segmentation can’t rescue a list full of invalid or risky contacts. Make hygiene a routine:

• Remove obvious bad addresses: role accounts (info@, sales@), known invalids, and repeated bounces.

• Use double opt-in for new leads when running high-volume ads or sweepstakes; it creates cleaner data and better inbox placement.

• Normalize preference capture: add a short form or a single-click interest tag to let subscribers choose product categories or frequency.

• Standardize UTM and source fields so you can compare engagement by acquisition channel and cut off the ones that add risk.

Step 6: Monitor the three metrics that matter

You do not need a huge dashboard. Watch these three every week, broken out by your three segments and top mailbox providers (Gmail, Yahoo, Outlook):

• Open rate (or inbox proxy): Is it stable for Active and improving for At-Risk?

• Spam complaint rate: Keep it at or under 0.1% of sends; if it rises, slow down At-Risk outreach.

• List churn: Combined unsubscribes + spam complaints as a percentage of total recipients; if it climbs, review your content and cadence.

If these numbers move in the right direction, revenue will follow.

A simple 30-day plan you can copy

Week 1

• Create Active (30D), At-Risk (31–90D), and Dormant (90D+) segments.

• Update all campaigns and flows to use these segments for includes/excludes.

• Audit the last 90 days of sends. If spam or bounce rates are high, reduce volume to At-Risk for now.

Week 2

• Build your sunset flow and turn it on.

• Draft two versions of the first email: light-design and plain text. Test which yields more “stay subscribed” clicks.

Week 3

• Launch the churn-risk save flow (predictive or proxy).

• Add a small perk for high-value customers only; keep costs low elsewhere.

• Add a basic preference capture link in your next campaign.

Week 4

• Review the metrics. Expect small improvements in open rate and a drop in spam complaints for campaigns that excluded Dormant.

• Document what you changed and schedule a follow-up review in 30 days.

Common pitfalls (and easy fixes)

• Sending to “all subscribers” by default
  Fix: Always start from Active Engagers, then decide if At-Risk is worth including for a given message.

• Over-using discounts to wake up inactive subscribers
  Fix: Lead with value content first; offer perks only for high-CLV customers in your churn-risk save.

• Ignoring Gmail/Yahoo behaviors
  Fix: If complaints or low opens come from a specific domain, slow down sends to that domain, especially for At-Risk.

• Treating SMS and email the same
  Fix: Mirror your recency tiers in SMS, but keep SMS frequency lower and value per message higher.

• One-and-done cleanup
  Fix: Automate hygiene. Your sunset flow, suppression rules, and preference capture keep your list healthy without constant manual work.

Frequently asked questions (quick answers)

What if my list is very small?
Start with a 45-day Active window instead of 30. You’ll keep volume up while still focusing on people who care.

What if my open rates dropped after I excluded Dormant?
Short term volume may dip, but inbox placement should improve. As reputation recovers, you’ll see higher opens and more sales from a smaller, healthier audience.

Can I re-warm Dormant subscribers later?
Yes, but do it carefully. Run a small re-permission test to a subset with clear value content. If engagement is weak, keep them out of regular campaigns.

Wrap-up

Deliverability improves when you respect attention. Segment by engagement, give unresponsive subscribers a polite off-ramp with a sunset flow, and reserve re-engagement offers for the customers who are actually at risk of leaving. With these pieces in place, you’ll protect your sender reputation, raise opens and clicks, and create a calmer, more profitable email program—without adding new tools or headcount.

If you want templates, copy the ideas above into your Klaviyo segments and flows today: one Active, one At-Risk, one Dormant, one Sunset, and one Churn-Risk Save. Keep it simple, measure weekly, and iterate.

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