Most advice about improving Klaviyo open rates focuses on subject lines. Subject lines matter — but they're the last thing you should optimise. If Gmail is filtering your emails into the Promotions tab or spam folder, the world's best subject line doesn't help.
These 9 tactics are ordered by impact. Start at the top.
📊 Benchmark first: Before making changes, run a free Klaviyo audit to get your deliverability score and see exactly what's dragging down your open rates.
The 9 Tactics
This single change typically improves open rates by 40–60% within 30 days. In Klaviyo, create a segment: "Opened Email in Last 90 Days OR Clicked Email in Last 90 Days OR Placed Order in Last 90 Days." Switch all campaign sends to this segment immediately. Sending to unengaged subscribers actively trains Gmail to deprioritise your emails for everyone on your list.
Go to mxtoolbox.com/dmarc.aspx and check your domain. If your DMARC policy is "p=none", you're at risk of spoofing and Gmail is likely deprioritising your emails. Update to "p=quarantine" in your domain registrar's DNS settings. This is a 15-minute change with potentially significant deliverability impact.
Klaviyo's Smart Send Time feature analyses when each individual subscriber historically opens emails and sends at their optimal time — rather than at a fixed time for everyone. Enable it in Flows → each email → Scheduling → Smart Send Time. Typically improves open rates 15–25% with no other changes.
In Klaviyo, go to Lists & Segments → Suppression List. Any subscriber with 2+ soft bounces, 1 hard bounce, or who hasn't opened or clicked in 180 days should be suppressed. Reducing your list size by removing dead weight counterintuitively improves open rates — because you're calculating against a cleaner denominator and improving your sender score simultaneously.
Before suppressing lapsed subscribers, run them through a win-back sequence. 4 emails over 40 days: no offer (Day 90), news/update (Day 105), best offer (Day 120), "last email" (Day 130). Brands doing this reactivate 8–15% of lapsed subscribers who would otherwise be lost — recovering real revenue before closing the door.
Once deliverability is clean, subject lines drive the final 15–20% of open rate improvement. The highest-performing formulas: Curiosity gap ("The email mistake costing you £3k/month"), Personalisation ("{{first_name}}, your order history says something"), Specificity ("3 products your customers buy together every time"), Urgency ("48 hours left — then this disappears"). Avoid: emojis in subject lines (they reduce deliverability in B2B), all-caps, and spam trigger words like "FREE".
By default, Klaviyo sends from shared infrastructure. A dedicated sending domain (e.g. mail.yourbrand.com) builds sender reputation specific to your brand rather than sharing it with thousands of other senders. Set it up in Klaviyo Settings → Email → Sending Domains. Takes 1 hour and has compounding impact over 60–90 days as your domain reputation builds.
Preview text appears next to the subject line in most email clients and contributes meaningfully to open rates. Most brands leave it empty (Klaviyo then pulls the first line of email copy, often an "unsubscribe" link or preheader code). Set preview text manually in the Klaviyo email builder for every email. Aim for 40–100 characters that extend or contrast the subject line rather than repeating it.
Tuesday–Thursday 9am–11am is the conventional wisdom. It's also what every other brand does, which means the inbox is most crowded then. Test Saturday morning (lower competition, higher attention) and Sunday evening (pre-week mindset) for your specific audience. Use Klaviyo's A/B testing on campaigns to run send-time tests over 4–6 sends before drawing conclusions.
✅ Quick wins summary: Tactics 1–3 (engaged segment, DMARC, Smart Send Time) can be implemented today in under 90 minutes and typically produce the biggest open rate improvements. Do these before anything else.
Klaviyo Open Rate Benchmarks by Industry
Open rates vary significantly by sector. Use these as context for your own figures:
- Fashion & Apparel: 18–24% (full list) / 32–40% (engaged segment)
- Food & Beverage / Coffee: 22–30% / 38–48%
- Health & Beauty: 20–28% / 35–45%
- Home & Garden: 18–25% / 30–40%
- Sports & Outdoors: 20–27% / 34–42%
If your engaged-segment open rates are below the lower bound for your industry, you have a deliverability issue — not a content issue. Focus on tactics 1–4 before anything else.
Find Out What's Dragging Down Your Open Rates
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