Clean Outbound Lists for Smartlead.ai.
Stop Campaign Auto-Pauses.
Smartlead automatically pauses client campaigns when bounce rates cross 3% to 5%. Verify your Apollo, Clay, and Sales Navigator lists with MailVeri before ingestion to keep client bounce rates strictly under 1.5% at $0.0002 per check.
Why Lead Gen Agencies Gate Smartlead Campaigns
When managing 50 to 500+ sender mailboxes across multiple client sub-accounts, a single dirty CSV upload can stall an entire client retainer.
Smartlead Bounce Auto-Pause
Smartlead's deliverability guardrails halt active campaigns automatically when hard bounces spike past your configured threshold (typically 3%–5%), disrupting client meeting flow.
Catch-All & Quota Isolation
MailVeri separates guaranteed VALID contacts from CATCH_ALL and over-quota FULL_INBOX recipients so primary client domains stay spotless.
Agency Margin Protection
Verifying 1,000,000 leads across 20 clients costs $3,199 on ZeroBounce vs $299 on MailVeri ($999 for 5M) — saving your agency over $30,000 per year in data hygiene overhead.
How to Connect MailVeri with Smartlead.ai
Use bulk CSV scrubbing for large campaign launches or real-time API verification for automated Clay/n8n lead streams.
Workflow A: High-Speed Bulk CSV Sanitization
Best for agency campaign managers launching weekly client sequences
Upload Client Lead CSV
Drop your Apollo, Clay, or LinkedIn export into the MailVeri Bulk Verifier. Supports up to 1,000,000 contacts per file.
Download VALID Segment
Export the VALID CSV for your primary Smartlead campaigns, and optionally export CATCH_ALL for secondary burner domains.
Upload to Smartlead
Upload into Smartlead with Ignore Global Block List disabled so client opt-outs and global bounces remain enforced.
Place a MailVeri HTTP check immediately before Smartlead's POST /api/v1/campaigns/{id}/leads action so undeliverable leads never enter active client sequences:
POST https://api.mailveri.com/v1/verify-mail/
Authorization: Bearer YOUR_MAILVERI_API_KEY
Content-Type: application/json
{
"email": "[email protected]"
}{
"error": 0,
"message": "Verified [email protected] successfully",
"status": "VALID",
"email": "[email protected]",
"mail": "[email protected]",
"is_disposable": false,
"is_role_account": false,
"is_catch_all": false,
"is_full_inbox": false,
"balance": 94210
}POST https://server.smartlead.ai/api/v1/campaigns/SMARTLEAD_CAMPAIGN_ID/leads?api_key=YOUR_SMARTLEAD_API_KEY
Content-Type: application/json
{
"lead_list": [
{
"first_name": "Elena",
"last_name": "Rostova",
"email": "[email protected]",
"company_name": "Vanguard Cloud"
}
],
"settings": {
"ignore_global_block_list": false,
"ignore_unsubscribe_list": false
}
}Deep-Dive Playbooks for Smartlead Agencies
How to Verify Emails Before Sending in Instantly & Smartlead (Keep Bounce Rate Under 1.5%)
Complete SOP for routing VALID, CATCH_ALL, and FULL_INBOX leads across agency domains.
Why Apollo “Verified” Emails Still Bounce (And How to Fix It)
See why raw Apollo exports cause 8%–18% bounce rates and trigger Smartlead auto-pauses.
How to Verify Emails in Clay Using HTTP API: Save 80% on Waterfall Credits
Gate your Clay AI columns and Smartlead export steps for 0 Clay credits.
Frequently Asked Questions
Everything outbound agencies need to know about verifying leads for Smartlead.ai.
Why did Smartlead auto-pause my client's campaign?
Smartlead monitors campaign bounce percentages and automatically pauses sending if bounces exceed the configured protection threshold (usually 3% to 5%). Pre-verifying lists with MailVeri and importing only VALID addresses keeps bounce rates below 1.5%.
Can I receive a webhook when a 500,000-row agency batch finishes?
Yes. MailVeri's Bulk API supports automated outbound webhooks that notify your backend, n8n, or Make workflow the exact moment a large CSV batch completes verification.
Do MailVeri credits expire between client campaigns?
Never. All MailVeri credits are pay-as-you-go and valid for life with zero monthly subscriptions, making it simple to buy bulk packages ($299 for 1M or $999 for 5M) and share them across all client accounts.
Keep every Smartlead campaign below 1.5% bounce
Create your free account in 30 seconds and test MailVeri with 1,000 free verification credits.