Keep your Klaviyo profiles clean and deliverable
Klaviyo automatically suppresses addresses that hard-bounce, but it can't judge a profile it has never sent to - and those never-mailed invalids are what quietly erode your deliverability and pad your active-profile count. Qualisend closes that gap: connect Klaviyo, verify the profiles in any list or segment, and optionally suppress the undeliverables so junk never reaches a send. Here's how the native connector works, plus the CSV, API, and no-code options.
Connect Klaviyo directly, no CSV needed
Connect in one click
Sign in to Klaviyo and approve access - no API keys to copy.
- Clean the profiles in any list or segment
- Results saved as properties, undeliverables optionally suppressed
- New subscribers checked in real time via webhook
- Auto-clean every 7, 14 or 30 days
Prefer CSV or the API? Both work too, see below.
What Klaviyo cleans for you
Klaviyo's native suppression handling is genuinely solid: an address that hard-bounces is suppressed automatically, one that soft-bounces more than 7 consecutive times (counted over the past two years) gets suppressed too, and unsubscribes and spam complaints become suppressed profiles that are excluded from every send. Suppressed profiles also stop counting toward the active-profile total Klaviyo bills on, so its own hygiene never inflates your invoice. For addresses Klaviyo has actually mailed, that's reliable automatic hygiene.
What it can't catch
The catch is that every one of those mechanisms is reactive - it needs a send, a bounce, or a complaint to fire. Never-mailed invalids from imports and signup forms, disposable inboxes that expired after grabbing a discount code, role addresses, and decayed mailboxes all look identical to a healthy profile in Klaviyo until your first campaign hits them - which is exactly when a mailbox provider forms its first impression of your domain. An imported list is the sharpest case: it arrives with its bounce history amputated, so addresses that were already failing on the old ESP come in looking brand new, and Klaviyo will happily mail all of them once.
Why a clean Klaviyo list matters
On Klaviyo the stakes are double, because Klaviyo prices on active profiles. Every dead address is a line item on your invoice as well as a drag on deliverability - undeliverable and disposable profiles push you toward the next pricing tier while pulling down the engagement rates that Klaviyo's own reputation model, and Gmail and Yahoo's 2024 sender rules, judge you on. Cleaning before a send does two jobs at once: suppressing the addresses you were never going to reach again can move you back under a pricing threshold, and it protects the inbox placement of the flows and campaigns that actually convert. The right order is verify first, import second - never mail an unverified list to find out.
Prefer CSV or the API? Here's the manual path
The native connector is the fastest route, but the CSV loop works on any Klaviyo plan: export from Klaviyo, verify in Qualisend, and act on the results.
Export your list from Klaviyo
Open the list or segment, choose Manage list → Export list to CSV, and download the file. Export the full list for a first clean; for maintenance, an "engaged never" or "created before" segment targets just the profiles most likely to have decayed.
Verify the file in Qualisend
Upload the CSV to Qualisend bulk cleaning - up to 1,000,000 addresses per job, duplicates charged once - or paste addresses directly. The free plan's 100 credits (they never expire) cover a first sample end to end.
Read the results
Every address returns deliverable, risky, undeliverable, or unknown with a reason code and sub-flags (catch-all, disposable, role, full mailbox), plus the domain's MX provider and probe detail as evidence. Download the cleaned CSV with the verdict columns included.
Suppress the undeliverables in Klaviyo
Filter the results to undeliverable, keep a single column with the header Email, then go to Profiles → View suppressed profiles → Import and upload it. Klaviyo recommends suppressing over deleting: suppression removes profiles from every send and from your active count, and unlike deletion it's reversible if you made a mistake.
Or automate it at signup
Prefer to keep junk out from the start? Verify at the point of capture with the Qualisend REST API (scoped keys, rate limits, webhooks), or wire a no-code flow through Zapier, Make, or n8n so new Klaviyo profiles are checked before they're ever created - which stops typos and disposables from entering your active-profile count in the first place.
What Qualisend flags on every address
- Never-mailed invalid addresses that would hard-bounce on your next campaign
- Disposable / throwaway domains built to expire after the discount code is claimed
- Role addresses (info@, billing@) that skew engagement-judged flows
- Catch-all domains, flagged so you can segment and throttle them
- A 0-100 confidence score and machine-readable reason code for every address
The native Klaviyo connector is live. Connect it in Qualisend under Integrations and work with your Klaviyo list directly, no CSV needed.
What to do with each result
Every address comes back with a verdict and sub-flags. Here's the action that keeps your Klaviyo list clean without throwing away contacts you can still reach.
deliverableKeep sending as normal.deliverable + role flagKeep for transactional and newsletter content; exclude from engagement-judged flows - a shared inbox skews your metrics.risky + catch-all flagMove to a dedicated segment and throttle your sends.risky + disposable flagSuppress - the inbox was built to expire.unknownLeave active and re-verify next clean - usually greylisting, not a verdict on the mailbox.undeliverableSuppress via the CSV import; don't wait for the bounce to prove it.Related reading
The full step-by-step: export, verify, and suppress the dead addresses.
Cleaning is half of deliverability - authenticate your sending domain too.
Verify at signup so junk never becomes a Klaviyo profile.
How fast a dirty list compounds into a deliverability problem.
Set a cadence sized to how your Klaviyo list grows.
The full picture beyond list hygiene.
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