Does Klaviyo verify emails, or do I need a separate tool?

Klaviyo is a sending platform, and its list hygiene works from what happens when you send. A hard bounce suppresses the profile. Bounce rate, spam complaints and unsubscribes feed the account's health measures. All of that is useful, and all of it starts after the damage is done. A verifier works earlier, while a dead address is still just a row in a file.

Stores feel this at three moments. A migration from another platform brings years of old addresses in one import. A signup popup collects typos like gmial.com. A purchased or co-registration list arrives with no history at all. Each one can push a single send past the bounce level that gets an account reviewed, and our Klaviyo bounce-rate guide shows where those levels sit.

For the import, export your profiles as CSV and upload the file to bulk verification. ZapBounce returns your original columns plus a result for each row: valid, invalid, catch_all or unknown, with role and disposable flags beside it. Store the result as a custom profile property, then build your main segment on valid. Our answer on verifying before a Klaviyo migration covers the move itself.

For signups, put a real-time check in front of the form. Your code calls POST /v1/verify on submit, and the did_you_mean field suggests a fix for a typo before the profile is created. A Zapier step on new profiles does the same job without code, and the Klaviyo integration page lists each route.

You'll pay $5 for 1,000 checks, or $25 for 10,000. Unknown results and duplicates cost nothing, and credits never expire, so a store that verifies each import and each month's signups spends from one pack.