Fixing Low Email Engagement · Part 2: Handle bounced email addresses (before Klaviyo has to)

July 14th, 2025

If you're working to improve email performance, bounced contacts—both soft and hard—deserve your attention.

Hard-bounced email addresses are automatically suppressed in Klaviyo, but they still point to a bigger issue: low-quality signups.

Soft bounces, on the other hand, can quietly hurt your sender reputation if you wait too long to act.

We put together a quick checklist to help you clean things up—and protect deliverability before more damage is done.

Hard vs. soft bounce (and how Klaviyo handles them)

📩 Hard Bounce:

The email can’t be delivered because the address is invalid (e.g. fake or mistyped).

→ Auto-suppressed by Klaviyo after 1 send

📪 Soft Bounce:

The email couldn’t be delivered due to a temporary issue (like a full inbox or server problem).

→ Suppressed by Klaviyo after 7 failed sends in a row

Soft-bounced emails ➡️ Exclude early

Don't wait for bounce #7. Klaviyo waits 7 failed sends to suppress soft-bounced email addresses—but if your deliverability’s already fragile, that delay can make things worse.

📍Step 1

Create a segment with: Email bounced → Bounce type = Soft ≥ 3 times

📍Step 2

Exclude this segment from campaigns while you rebuild deliverability.

💡Once your deliverability improves, you can try sending again (e.g. their inbox may no longer be full). If the sent emails still bounce, Klaviyo may suppress—or you can suppress/delete those contacts manually.

Hard-bounced emails ➡️ Clean up fast

Remove known bad addresses. Hard-bounced email addresses are already suppressed by Klaviyo, but deleting them helps keep your list clean and your segmentation accurate.

📍Step 1Create a segment: Email bounced → Bounce type = Hard → Over all time

📍Step 2Go to: Account Settings → Other → Profile Maintenance→ Select your segment under “Remove Profiles”→ Confirm deletion

Next steps & what's coming

In the next email, we’ll show you how to prevent hard bounces in the first place—so fewer bad addresses land on your list to begin with.

Until then:

🔧 Use our checklist to clean up your list

📞 Or book a call if you’d rather hand it off

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