Keep your Omnisend audience clean, deliverable, and off your bill
Omnisend automatically unsubscribes hard bounces, but it can't judge an address it has never sent to - and on Omnisend those never-mailed invalids usually sit in your account as non-subscribed contacts that quietly count toward your bill. Qualisend closes that gap: connect Omnisend, verify your subscribed contacts or any segment, and act on the dead ones before your first campaign hits them. Here's how the native connector works, plus the CSV, API, and no-code options.
Connect Omnisend directly, no CSV needed
All you need is an API key
Paste an Omnisend API key with Contacts access. Create one on Omnisend's API keys page.
- Clean all subscribed contacts or a segment
- Results saved as custom properties on each contact
- New subscribers checked in real time (paid Omnisend plans)
- Auto-clean every 7, 14 or 30 days
Prefer CSV or the API? Both work too, see below.
What Omnisend cleans for you
Omnisend's native hygiene runs on automatic status changes. When an address hard-bounces, Omnisend marks it bounced and unsubscribes it - one of its automatic unsubscribe reasons - so it drops out of every future send; an address that keeps soft-bouncing is suppressed after repeated failed attempts. Crucially, Omnisend separates unsubscribed (actively opted out) from non-subscribed (never opted in), and it does not automatically remove or suppress non-subscribed contacts. For addresses Omnisend has actually mailed, that's dependable automatic hygiene.
What it can't catch
The catch is that every one of those mechanisms is reactive - it needs a send and a failure to fire. Never-mailed invalids from imports and signup forms, disposable addresses, role addresses, and decayed mailboxes all look healthy until your first campaign hits them, which is exactly when a mailbox provider forms its first impression of your domain. On Omnisend the import is the sharpest case: a list arrives with its bounce history stripped, so addresses that were already failing elsewhere look brand new - and they land in your account as non-subscribed contacts that count toward your billable total from day one, before a single send has proved them dead.
Why a clean Omnisend list matters
On Omnisend the stakes are twofold, because of how Omnisend bills. It counts your billable contacts on each billing day as your subscribed plus non-subscribed contacts - non-subscribed count because they can still receive transactional automations like order confirmations. The only status excluded from billing is unsubscribed. So a dead never-mailed address imported as a non-subscribed contact costs you every billing cycle until you act on it, while it also drags down the engagement rates Omnisend's own reputation model, and Gmail and Yahoo's 2024 sender rules, judge you on. Cleaning before a send does two jobs at once: it can move you under a plan tier, and it protects the inbox placement of the automations that actually convert.
Prefer CSV or the API? Here's the manual path
The native connector is the fastest route, but the CSV loop works on any Omnisend plan: export from Omnisend, verify in Qualisend, and act on the results.
Export your audience from Omnisend
Open Audience, filter to the segment you want to clean (or export the whole audience for a full maintenance pass), and export it to CSV.
Verify the file in Qualisend
Upload the CSV to Qualisend bulk cleaning - up to 1,000,000 addresses, duplicates charged once - or paste addresses directly. The free plan's 100 credits cover a first sample.
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 MX provider and probe detail as evidence. Download the cleaned CSV.
Retire the undeliverables in Omnisend
Filter your results to undeliverable, then unsubscribe those contacts - which stops sends and removes them from your billable count, since unsubscribed is the one status Omnisend doesn't bill for - or delete them outright. Don't wait for the bounce to prove what verification already showed.
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 Omnisend signups are checked before they ever become billable non-subscribed or subscribed contacts.
What Qualisend flags on every address
- Never-mailed invalid addresses that would hard-bounce on your next Omnisend campaign
- Disposable / throwaway domains accepted at signup and built to expire
- Role addresses (info@, support@) that skew engagement-judged automations
- 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 Omnisend connector is live. Connect it in Qualisend under Integrations and work with your Omnisend 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 Omnisend list clean without throwing away contacts you can still reach.
deliverableKeep sending as normal.deliverable + role flagKeep for transactional content; exclude from engagement-judged automations.risky + catch-all flagMove to a dedicated segment and throttle your sends.risky + disposable flagUnsubscribe or delete - the inbox was built to expire.unknownKeep and re-verify next clean - usually greylisting or rate-limiting, not a verdict on the mailbox.undeliverableUnsubscribe (which also takes them off your bill) or delete; don't wait for the bounce to prove it.Related reading
The full step-by-step: export, verify, and unsubscribe or delete the dead addresses.
Cleaning is half of deliverability - authenticate your sending domain too.
Verify at signup so junk never becomes a billable Omnisend contact.
How fast a dirty list compounds into a deliverability problem.
The full picture beyond list hygiene.
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Keep your CleverTap audience deliverable before the campaign fires, not after the bounce
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Omnisend verification FAQ
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