ZapBounce

ZapBounce and Klaviyo

Klaviyo is built around profiles rather than lists, and it keeps its own view of your sending health. A dirty import costs you more than one campaign: it moves a score the platform then uses to shape everything after it.

Ecommerce data makes this sharper. Profiles arrive from checkout, from popups and from a previous platform, and the three sources fail in different ways.

Klaviyo's deliverability view is shaped by what you import

Klaviyo surfaces bounce rate, spam complaint rate and unsubscribe rate as ongoing health measures, and it suppresses addresses after hard bounces without asking. Those suppressions are permanent for that profile unless you intervene.

The consequence is that a bad import is not reversible in the way a bad campaign is. Profiles suppressed on a bounce stay suppressed, and if a real customer was suppressed because of a typo they never receive another flow.

Klaviyo also warns against importing unengaged profiles, because it assesses sending reputation across the account. On a shared-infrastructure setup that means one bad import affects sends that have nothing to do with the list you imported.

How the data moves

  1. Decide between CSV import and the profiles API

    For a one-time clean, export profiles as CSV and verify the file. For continuous checking, verify before the profile is created through the API, so nothing unverified ever enters.

  2. Store the verdict as a custom profile property

    A property rather than a list membership, because properties are queryable in segment conditions and survive list changes.

  3. Build segments on the property

    A segment where the verdict property equals valid gives you a clean sending audience without deleting anything. Catch-all profiles get their own segment and their own flow.

  4. Check at the signup form

    Klaviyo's own forms post to its API. Put the verification in front of that call rather than after, so a mistyped address never becomes a profile that gets suppressed on the first send.

Setting it up

  1. Export profiles from Klaviyo, or pull them through the profiles API if the account is small enough.
  2. Verify the file, keeping every existing property column so the verdict lands beside the profile data.
  3. Create a custom property on profiles for the verdict, and one for the check date.
  4. Import the results back, matching on email so existing profiles update rather than duplicate.
  5. Create a segment with verdict equal to valid and point your main flows at it.
  6. Create a second segment for catch-all profiles and send to it separately, watching its bounce rate on its own.

Klaviyo: common questions

Will verifying stop Klaviyo suppressing profiles?

It removes the addresses that would have hard bounced, which is the main cause of suppression. Complaints and unsubscribes are unaffected.

Should I delete invalid profiles or suppress them?

Suppress. The profile carries order history that is worth keeping, and it is the address that has stopped working rather than the customer.

Does this help with a Klaviyo deliverability review?

It removes one input. Sending consistency, authentication and the age of the list all matter too, and verification does not touch any of them.

Reference

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