Clean a Shopify and Klaviyo List Before a Sale Send: What to Do With Each Result
To clean a Shopify or Klaviyo list before a sale, export the profiles as a CSV, verify every address, then suppress invalid rows, send first to valid ones and test risky rows in a small batch. A sale is the one send where your whole list gets a message at once, so a high bounce rate shows up when volume is highest. The email verification for e-commerce stores page covers the mailbox check; the Shopify export guide and Klaviyo export guide show where the CSV lives.
Step 1: export
Pull customers from Shopify and subscribers from Klaviyo, then merge them. The same buyer can be in both. The Klaviyo email list cleaner and Shopify email list checker do a first pass in your browser.
Step 2: verify
Upload the CSV on the verify page. For each row you get valid, risky or invalid with a reason.
Step 3: decide per reason
| Reason | What it is | What to do before the sale |
|---|---|---|
| Mailbox not found | The mailbox is gone | Suppress |
| No mail server | The domain does not take mail | Suppress |
| Typo domain | A checkout slip such as gmial.com | Fix and re-check, or suppress |
| Disposable address | A throwaway used for a first-order code | Suppress or keep out of the main send |
| Accepts all addresses | Catch-all domain | Include in a later batch |
| Role address | Shared inbox | Usually fine for a store; your call |
| Valid | Mailbox exists | Send |
Step 4: put the result back
Import suppression back into Klaviyo. The Klaviyo suppressed profiles guide explains how suppression behaves, and the suppression list merger combines lists from several tools. For Shopify, see email bounce suppression in Shopify.
Step 5: stage the send
Send to engaged valid rows first, then widen. The Black Friday list prep checklist gives a two-week plan, and the Klaviyo bounce rate guide shows where to watch results.
What this cannot do
- A valid result is a snapshot; a mailbox can close afterwards.
- Yahoo and AOL accept mail for any address during the check, and Microsoft consumer mailboxes are not probed, so those rows come back risky.
- It cannot tell you who will open or buy.
Clean it before the sale
Upload your export on the verify page: the first 100 checks are free with a Google sign-in, no card. For larger lists, see bulk email verification and pricing.
Common questions
How do I clean a Klaviyo or Shopify list before a sale?
Export the profiles as a CSV, verify every address, then suppress invalid rows, send first to valid rows and test risky rows in a small batch.
Should I delete invalid addresses?
Suppress them rather than delete them. A suppressed profile keeps its purchase history but is not emailed, and it stops the same address being re-imported later.
What is a risky result for a store?
The domain takes mail but the mailbox could not be confirmed. The usual reasons are Accepts all addresses, Role address, and providers such as Yahoo, AOL or Microsoft consumer mailboxes that do not allow an honest check.
How early should I do it?
Early enough to send the cleaned list a warm-up email before the big send. The Black Friday checklist on this site sets out a two-week plan.
How much does it cost?
The first 100 checks are free with a Google sign-in, no card. Pro is $39 a month, with the first 100,000 checks a month at full speed, then slower, never cut off.
Check your list before you send
Real mailbox checks over SMTP, and nothing is sent to the address. Sign in with Google and your first 100 email checks are free, no card. Plans for bigger lists are on the pricing page.