Klaviyo is more expensive now. Every active profile on your list contributes to your monthly bill. And if a chunk of those people hasn’t opened an email in months, you’re paying to speak into the void.

We’ll walk through a clean, automated system to fix that: re-engage cold subscribers, suppress who doesn’t respond, and reduce your monthly bill — all without hurting revenue.

This article is partnered with Gavin Hewitson from In-box.

Define Your “Unengaged” Segment the Right Way

What “unengaged” means for your brand:

• Has received at least 10 emails overall
• Has opened 0 emails in the last 90 days
• Has placed 0 orders overall (optional — but helps avoid suppressing recent customers)

Once you’ve built this segment, take action: try to win them back, or suppress them to lower your cost.

Send Two Plain Text Re-Engagement Emails

Try one last reactivation attempt:

• Write two plain text emails — no design, no images
• Send them 2–3 days apart
• Use a sender name that sounds human (e.g., “Jake from [Brand Name]”)

Subject lines like “Should we stop contacting you?” can perform well. The goal is to make the email feel personal and prompt a click, reply, or open — any engagement that removes them from the unengaged segment.

Suppress Unresponsive Subscribers

After sending your re-engagement emails and waiting 24 hours, it’s time to act.

Create segments that should be suppressed.

• Remains in the unengaged segment
• Didn’t open or click either email

By suppressing them manually or building a segment for monthly suppressions, you can massively reduce your email marketing overhead without touching your active list.

Automate the Whole Process with a Sunset Flow

It’s not sustainable to do this manually every month. So — automate:

• Create a new flow in Klaviyo
• Trigger: when someone enters the Sunset (unengaged) segment
• Add two plain text emails spaced 3 days apart
• Set a delay of 24 hours after the second email
• Update the profile to tag the user (e.g., “Suppressed”)

You can also add profile filters to see whether they opened, clicked, or placed an order since entering the flow. If not, they move to the final stage and get tagged for suppression.

(Not sure how your email performance stacks up? This ecommerce email benchmarks guide can help you spot what’s working and where to improve.)

For Aimerce Customers

When paired with Aimerce, you can maximize the revenue of your existing profiles without increasing the cost. You’ll be able to use rich customer data to trigger flows, customize messaging, and optimize timing — without lifting a finger.

Aimerce tracks each of the profile for longer, so Klaviyo receives the full context — like who’s browsing vs. who’s truly disengaged.

Final Thoughts

Trimming your list doesn’t mean losing revenue. In fact, it’s usually the opposite: suppressing unengaged users improves deliverability, focuses your efforts on high-quality contacts, and cuts unnecessary spend.

Save every month — you just need to set it up once.