Clean your list before importing into Klaviyo

Why Klaviyo lists need verification before import

Klaviyo is an ecommerce marketing platform built around profiles: every email address becomes a profile that flows can target, and your plan is priced on active profiles. That pricing model means dead and fake addresses cost you twice — once in inflated billing, and again in deliverability damage when your flows send to them. Klaviyo also watches engagement and bounce metrics closely, and consistently poor numbers hurt inbox placement for your whole store.

Ecommerce lists get dirty fast. Popup forms invite typos and throwaway addresses in exchange for a discount code, migrated lists carry years of decayed mailboxes, and abandoned-cart captures often hold half-finished entries. When Klaviyo's welcome or win-back flow fires against those, the bounces land against your sending domain and Klaviyo's deliverability grading, quietly pushing your promotional email toward the spam folder across your engaged customers too.

Verifly checks each address with a live mailbox probe and returns deliverable, undeliverable, or risky with disposable, role, and catch-all flags. Verify before importing profiles into Klaviyo, and you keep your billable profile count honest, your bounce rate low, and your store's sender reputation strong.

Verify before importing profiles

1. Export the list you plan to import as a CSV, or capture form submissions before they create a Klaviyo profile.
2. Get a free key at verifly.email/api/v1/autonomous/register — 100 credits, no card, no captcha.
3. POST the email column to /verify/batch for the whole list, or GET /verify per submission at the popup form.
4. Import only deliverable rows. Dropping undeliverable and disposable addresses also keeps your billable profile count lean.
5. Let your Klaviyo flows run against real shoppers, then re-verify bounced profiles before any win-back attempt.

const emails = migratedList.map(r => r.email)

const res = await fetch('https://verifly.email/api/v1/verify/batch', {
  method: 'POST',
  headers: {
    'Authorization': 'Bearer vf_your_api_key',
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({ emails }),
})

const { results } = await res.json()
const profiles = results.filter(r => r.result === 'deliverable')
console.log(`Creating ${profiles.length} clean Klaviyo profiles`)