Email is more important than ever in 2025. Your customers are expecting to hear from you, but they want relevance. They want timing. And most of all, they want it to feel like you’re talking to them, not at them. That kind of organic, high-converting communication doesn’t happen by accident. It starts with smart segmentation.

Segmentation is the foundation of personalization. Without it, your messages are generic at best or completely off-base at worst. And when your segmentation is ineffective, you’re behind before you even hit send.

We spoke with Ben Zettler, founder of Zettler Digital and longtime Klaviyo Elite Partner, about how the fastest growing ecommerce brands are approaching segmentation today. These aren’t abstract best practices, these 7 tactics are proven plays you can put into action right now:

1. Suppress Dormant Email Subscribers for Increased Deliverability

Dormant users are the silent killers of deliverability. If someone has been subscribed for 6+ months, received 10+ emails, and never clicked, it’s time to stop emailing them.

Suppress or exclude these users from campaigns to instantly improve inboxing, cut costs, and refocus your efforts on people who might actually convert.

2. Exclude Soft Bounces to Protect Your Email List Health

Soft bounces can also damage deliverability if ignored. If someone bounced in the last 30 days but isn’t suppressed yet, don’t hit them again right away.

Exclude soft bouncers from recent campaigns and reintroduce them later with re-engagement strategies.

3. Segment by Purchase History to Personalize the Customer Journey

Your customers aren’t all in the same stage of the journey so don’t treat them like they are.

Create segments for one-time buyers, active subscribers, never-purchased users, holiday-only shoppers, and more. What converts a loyal customer isn’t what converts a new prospect, your segments should reflect that.

4. Use Zero-Party Data to Personalize Emails

Simple questions like “How do you take your coffee?” or “What is your favorite color?” increase form submissions and give you real data to personalize the journey. Use that info to power conditional flows or send different content based on user preferences.

5. Segment Based on Real Engagement, Not Inflated Open Rates

Recent iOS privacy updates changed how open rates on emails are tracked. But you can still segment based on real activity, like clicks and confirmed opens.

This helps you identify who’s paying attention and avoid wasting sends on vanity metrics.

6. Throttle Email Send Times to Avoid the Spam Folder

Planning a blast to 10,000 users at once? You’re asking for spam folder trouble.

Instead, use gradual sending windows to space out delivery over several hours. This improves deliverability and keeps your emails in the inbox, not the spam folder.

7. Leverage Product Affinity to Drive Repeat Purchases

Use past purchase data to identify what customers are most likely to buy next.

For example, if someone bought a sweater in blue, and you now have the same product in green, they’re prime for a cross-sell message. Use product affinity to build smarter segments and drive repeat purchases.

What Do I Do With My List Once It’s Segmented?

Once you implement these seven segmentation tactics, you’re not just improving your deliverability or sending fewer emails. You’re building a set of high-impact, ready-to-use segments that drive real revenue.

“The difference between a good message and a great one usually comes down to timing and targeting.” - Ben Zettler, Founder, Zettler Digital

Here’s how some of those tactics directly lead to smarter audience slices:

Email Segment: High-Intent Window Shoppers

• Definition: Users who clicked an email or browsed your site in the past 7 days but didn’t buy.
• Engagement segment: Identify users who clicked but didn’t convert.
• Product affinity segment: Match their browsing behavior with what they’re most likely to buy next.
• Use this segment for: timely nudges, personalized product recommendations, or limited-time offers.

Email Segment: Preference-based subscribers

• Definition: Users who opted in via a quiz or popup and shared specific product preferences.
• Zero-party data segment: “How do you take your coffee?” becomes a powerful segment trigger.
• Engagement segment: Combine preferences with click activity to refine even further.
• Use this segment for: personalized welcome flows, interest-based campaigns, or new product drops.

Email Segment: Lapsed VIPs

• Definition: Once-loyal customers who haven’t purchased in 90+ days.
• Purchase history segment: Filter for high past value, now inactive.
• Product affinity segment: Remind them of what they loved, then offer what they’d like next.
• Use this segment for: winback flows, personalized reminders, or bounceback offers.

Use AI Agents to Segment and Target For You

All seven of these segmentation tactics are proven to work. The challenge is most brands don’t have the time or the team to execute them consistently.

That’s where AI marketing agents come in. Instead of manually building segments, suppressing users, and guessing which message goes to whom, AI agents handle it all in real time.

They identify the right users, personalize the content, choose the best channel, decide on optimal timing, and continuously learn based on performance. You get smarter targeting, higher efficiency, and better results, automatically.

If your team is strapped for time or stuck in the weeds, let Monocle’s AI agents handle the segmentation and personalization for you.

“AI isn’t here to replace marketers, it’s here to free them up to focus on the big stuff.” - Ben Zettler, Founder, Zettler Digital

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