Most Shopify stores segment their list into "customers" and "everyone else" and stop there, which leaves most of Klaviyo's actual value on the table. Real segmentation uses engagement recency, purchase behavior, and browsing activity together, not list membership alone, and it's the difference between a campaign that feels relevant and one that reads as a mass blast.
Why "Customers vs Non-Customers" Isn't Enough
That split treats a customer who bought once eighteen months ago the same as one who bought last week, and treats a subscriber who opens every email the same as one who hasn't opened anything in six months. Both pairs need completely different messages, and a two-bucket segmentation can't tell them apart.
The Segments That Actually Matter
- Engagement recency. Opened or clicked in the last 30-60-90 days. This protects deliverability as much as it targets revenue, mailing genuinely unengaged profiles repeatedly is one of the fastest ways to end up in spam folders for everyone, including your engaged subscribers.
- Purchase recency and frequency. First-time buyers, repeat buyers, and lapsed buyers each need a different message. A first-time buyer needs trust-building; a repeat buyer can handle a more direct sell; a lapsed buyer needs a reason to come back, not a generic promo.
- Product category affinity. A customer who's only ever bought from one category doesn't need every campaign, only the ones relevant to what they've actually shown interest in.
- Predicted lifetime value. Klaviyo can estimate this from purchase behavior, and it's a legitimate way to prioritize who gets a VIP-style offer versus a standard one.
Segmentation isn't really about targeting more precisely for its own sake. It's about not sending the same message to someone who just bought and someone who hasn't opened an email in a year, they need almost opposite things from you.
The Deliverability Case, Not Just the Revenue Case
Sending every campaign to your entire list, including profiles that never engage, drags down your overall open and click rates, and inbox providers read a pattern of low engagement as a signal to start filtering your emails into spam, for everyone on the list, not just the unengaged portion. A basic engagement segment (mail only those active in the last 90 days for most sends, with a separate lighter cadence for the rest) protects the inbox placement of every campaign you send.
Still sending every campaign to your whole list?
I'll set up segmentation based on real behavior, not just who's purchased before.
Where to Start
Don't try to build all of this in one pass. Start with an engagement recency segment and use it to gate your next few campaigns, that single change protects deliverability immediately. Layer in purchase recency next, then category affinity once the basics are actually running. Segmentation compounds; it doesn't need to be perfect on day one to start paying off.