Lists versus segments in Omnisend
Before touching any filters, you need to understand the structural difference between a list and a segment. A list is a static bucket of contacts who gave you their details. Unless someone joins via a form or gets deleted, that list sits there unchanged.
Segments are completely dynamic. They are rule-based groups that update in real time based on customer behaviour, profile properties, and purchase history. When someone takes an action, they enter the segment. When their activity drops off, they fall out automatically.
Treating lists and segments as the same thing is a mistake. If you send marketing campaigns to static lists, your deliverability will suffer because you end up blasting unengaged inboxes.
The two segments you will actually send to
Brands tend to overcomplicate their campaign audience strategy. In reality, roughly 90% of your weekly campaign volume should go to two specific groups: engaged 90-day customers and engaged 90-day non-customers.
Separating buyers from non-buyers is the simplest way to personalise your messaging. Customers already trust your brand, so you can speak to product benefits, loyalty perks, and cross-sells. Non-customers need social proof, objection handling, and maybe a first-order incentive.
Both segments rely on the same engagement baseline. You only want to reach people who have interacted with your brand recently enough that mailbox providers view your emails as wanted mail.
The Omnisend logic quirk you need to know
Omnisend offers roughly 95% of the core functionality you get in Klaviyo, and it does it at a significantly more competitive price point. However, the segment builder has one specific quirk you need to watch out for when mixing conditions.
If you try to drop an AND condition straight beneath an OR condition in the same block, the builder can force every rule in that block to become an AND condition. That breaks your logic immediately.
To fix this, you have to cluster your conditions intentionally. You group all your OR engagement rules into one clear block, and then use the clone or add-block function to layer your AND purchase conditions separately above or below it.
Step-by-step: building an engaged customer segment
To build your 90-day engaged customer segment in Omnisend, head to the left-hand sidebar, click Segments, and hit Create Segment. You can ignore the generic pre-built presets for now.
Start by setting up your engagement criteria within the first group:
- Opened message: at least once in the last 90 days
- OR Clicked message: at least once in the last 90 days
- OR Subscribed to email marketing: in the last 30 days
That 30-day subscription window ensures brand-new subscribers who have not had 90 days to open campaigns still get your messages. Next, add a separate AND condition block right beside it.
In that second block, set Placed order to at least once over all time. Save the segment and give it a clear name. It is that simple.
Adapting for non-customers and recent subscribers
Once your customer segment is live, building the non-customer version takes less than two minutes. You keep the exact same engagement rules and flip the purchase filter.
Duplicate your engaged customer segment and change the purchase condition from placed order at least once to placed order zero times over all time. This isolates everyone who is reading your content but has never completed a checkout.
Here is why this separation works: you can run the exact same promotional campaign to both groups on a Thursday afternoon, but tailor the subject line and offer to match their intent. Your open rates will climb, and your unsubscribe rate will drop.
Final Thoughts
You do not need fifty complex segments to drive serious revenue from your campaign calendar. Start with clean, dynamic 90-day engagement segments split by purchase history, and keep your logic blocks tidy. Once that foundation is solid, your deliverability handles the rest.
Put your segmentation to work
If you want expert help dialing in your segmentation, cleaning up your deliverability, and building campaigns that convert, take a look at our email campaign management service.
