Does Qualisend have a native Marketo integration?

A native one-click connector is being rebuilt as part of our platform upgrade and will return. Today the supported path is the CSV loop — build a smart list, export from Marketo, verify in Qualisend, then suspend or delete — or verifying at capture through the API. Both work with any Marketo Engage plan.

Will cleaning my list lower my Marketo bill?

It can, but only if you delete. Most Marketo agreements are priced on database size, and both a Marketing Suspended lead and an Email Invalid lead still occupy a record — so they still count. Verifying and then deleting the genuinely undeliverable and expired-disposable leads (after saving the cleaned CSV) is what actually reduces the number you're billed on. Verifying before an import keeps that junk out of the count from the start.

Should I suspend or delete an invalid lead?

Suspend when you want to keep the record's history — activity log, program membership, sales notes — and just stop the sends; good for role addresses, catch-alls, and leads sales still references. Delete the genuinely dead records you'll never use again, since on a database-size plan only deleting removes them from the count. Export the verified CSV first so you keep proof the address was bad and won't silently re-import it later.

Does Marketo's Email Invalid flag shrink my database?

No. A flagged lead stays in your database and stays billable until you suspend or delete it — Email Invalid stops the sends, not the billing. That's why an export-and-verify pass pays for itself twice: once in deliverability, and once at renewal when you delete the dead records the flag left in place.

Can I verify leads before they enter Marketo?

Yes — it's the highest-leverage option. Verify at capture through the REST API (or a Zapier/Make/n8n flow) so typos and disposable addresses never enter Marketo, never become billable records, and never bounce on your first send. It's the same clean data the CSV loop produces, applied before the lead lands.

Native connector returning — CSV & API work today

Clean your Marketo database — and shrink what you pay for

Marketo flags a lead as Email Invalid the moment it hard-bounces and stops mailing that address — but it can't judge a lead it has never sent to, and on a plan billed by database size those never-verified records cost you twice: in deliverability and at renewal. Qualisend closes that gap: export a smart list, verify every address, then suspend or delete the dead records so junk never reaches a send — or your invoice. Here's the workflow that works today, plus the API and no-code options.

Clean a list for free Read the Marketo guide

One-click Marketo sync is paused while we rebuild the platform

We've deliberately paused our one-click native connectors while we re-engineer the sync layer they run on — hardening how we authenticate, respect each platform's rate limits, and write results back — so that when the native Marketo integration returns, it stays dependable at any list size rather than fragile at scale. None of this touches how Qualisend verifies an address.

Everything you need works today: the CSV export → verify → reimport loop below, and the API for verifying at signup, are both fully supported and running in production — that's how teams keep Marketo clean right now.

Marketo handles

What Marketo cleans for you

Marketo's native hygiene centers on one field: Email Invalid. When a lead hard-bounces, Marketo sets that person's Email Invalid field to true, records an Email Invalid Cause, and stops sending marketing email to the address — and because it's an ordinary field, you can build a smart list that returns every invalid lead in the database. A separate Marketing Suspended field lets you bench an address without deleting the record. For addresses Marketo has actually mailed, that's real, automatic hygiene.

The gap it leaves

What it can't catch

The catch is that every one of those mechanisms is reactive — it needs a send and a bounce to fire. Never-mailed invalids from list buys, event-badge scans, and other automation platforms, plus old form fills and signup typos, have never bounced because they've never been sent to. Disposable addresses, role addresses, and decayed B2B mailboxes — the first.last@company.com that converted last year and became a hard bounce the day that person changed jobs — all look perfectly healthy in Marketo today. An imported list is the sharpest case: it arrives with its bounce history stripped, so addresses that were already failing on the old platform look brand new — and each one lands in the database you're billed on.

Why a clean Marketo list matters

On Marketo the stakes are double, because most Marketo Engage agreements are priced on database size. A dead lead is a line item on your invoice as well as a drag on deliverability — and the trap is that neither Marketo's own Email Invalid flag nor a Marketing Suspended lead removes the record, so both keep costing you until you delete. Meanwhile that never-verified address is what a mailbox provider meets first: your opening campaign is where Gmail and Yahoo's bounce and complaint thresholds, and Marketo's own engagement scoring, form their impression of your domain. Cleaning before a send does two jobs at once — it can pull you under a database tier at renewal, and it protects the inbox placement of the programs that actually convert.

The workflow that works today

Direct connectors are paused while we rebuild the platform, so the dependable path is the CSV loop: export from Marketo, verify in Qualisend, reimport the clean file.

Build a smart list and export from Marketo

In your Lead Database, build a smart list for the segment you want to clean — everyone, a single acquisition source, or one program's members — and export the view to CSV with the email column. For a maintenance pass, a smart list that excludes leads already flagged Email Invalid keeps the file down to just the unknowns.

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 a 0–100 score, plus sub-flags (catch-all, disposable, role, full mailbox) and the MX provider and probe detail as evidence. Download the cleaned CSV.

Suspend or delete the dead leads in Marketo

Re-import the cleaned file to populate a custom field like Verification Status, or match on email to set Marketing Suspended on the undeliverables. Suspending stops every marketing send immediately, but the record still occupies your billable database; deleting the genuinely dead records is what actually shrinks your database-size count — save the verified CSV as your archive first.

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 a new form fill or synced lead is checked before it ever becomes a billable Marketo record — no typo or disposable address gets in to bounce on the first campaign.

What Qualisend flags on every address

Never-mailed invalids from imports, list buys, and event scans that would hard-bounce and flip Email Invalid on your next campaign
Decayed B2B mailboxes — a lead who changed jobs since import looks healthy in Marketo until the send bounces
Disposable / throwaway domains dropped into a gated-content form to grab the asset
Role addresses (info@, sales@) that skew Marketo's engagement scoring and behavioral triggers
Catch-all domains, flagged so you can build a dedicated smart list and throttle them
A 0–100 confidence score and machine-readable reason code on every address

Native connector status

A native, one-click Marketo connector is part of the platform we're rebuilding — it's returning, not deprecated; until it ships, the CSV loop above and the API are the fully supported path, and they work with any Marketo Engage plan.

What to do with each result

Every address comes back with a verdict and sub-flags. Here's the action that keeps your Marketo list clean without throwing away contacts you can still reach.

deliverableKeep mailing as normal.

deliverable + role flagKeep for account and transactional touches; exclude from engagement-scored programs.

risky + catch-all flagMove to its own smart list and throttle — a catch-all accepts everything at the door, so a single send proves little.

risky + disposable flagSet Marketing Suspended — the inbox was built to expire.

unknownKeep active and re-verify next clean — usually greylisting or rate-limiting, not a verdict on the mailbox.

undeliverableSuspend or delete; on a database-size plan, delete the genuinely dead to take them off your billable count. Don't wait for the bounce to set Email Invalid for you.

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