StopBouncingVerify every client list before it touches an ESP
EU-hosted SMTP verification for email marketing and lead generation agencies. CSV upload and REST API. No subscription — pay per verification, credits never expire.
Everything an agency needs
Designed for teams that manage email lists on behalf of multiple clients.
Bulk CSV verification
Upload client lists in CSV, TXT, or Excel format. Multi-column files are handled automatically — no reformatting needed. Duplicates are removed before processing so you never pay twice.
REST API for automation
Integrate directly into your onboarding flow, CRM, or lead generation pipeline. One GET request returns a result in under 2 seconds. Bearer token auth, 60 req/min per key.
EU hosting — GDPR compliant
All processing happens on EU-based servers. Uploaded lists are cleared immediately after processing. Results available for 7 days, then permanently deleted. DPA available on request.
SMTP-level verification
We go beyond syntax checks — a live SMTP handshake confirms whether the mailbox actually accepts mail. Catch-all detection, disposable email detection, and role-address flagging included.
No subscription required
Credits never expire. Buy a pack when a client project requires it — no monthly commitment, no minimum spend, no renewal costs. Pay only for what you actually verify.
Results your clients can use
Downloads include all original columns plus a status column — ready to import directly into Klaviyo, Brevo, Mailchimp, HubSpot, or any ESP. Five status values: valid, invalid, unknown, disposable, role.
Who uses StopBouncing
Agencies across the marketing and lead generation stack.
Email marketing agencies
Clean client lists before every campaign. Protect sender reputation across all accounts you manage. One verification run before a campaign pays for itself the first time a client avoids an ESP suspension.
B2B lead generation agencies
Deliver clean, verified contact data to clients. Use the API to verify at the point of capture before leads enter a CRM. Filter out disposable addresses and role accounts that will never convert.
CRM and automation consultancies
Integrate verification into onboarding flows, HubSpot workflows, or n8n/Make automations. The REST API works with any HTTP-capable tool. Real-time verification at signup — not just before campaigns.
From list to clean results in three steps
Upload the list
Drag-and-drop a CSV, TXT, or Excel file. Multi-column files are handled automatically — no reformatting required. Duplicates removed before processing begins.
SMTP verification runs
Every address is checked via live SMTP handshake. Disposable and catch-all domains are flagged. You receive an email when the job completes.
Download the results
The results file preserves all original columns and adds a status column — valid, invalid, unknown, disposable, or role. Ready to hand to a client or import into any ESP.
Simple credit-based pricing
No monthly fee, no commitment. Buy a credit pack when you need it — credits never expire.
€18
10,000 credits
€0.0018/email
€35
25,000 credits
€0.0014/email
€52
50,000 credits
€0.0010/email
€99
100,000 credits
€0.00099/email
€180
250,000 credits
€0.00072/email
€600
1,000,000 credits
€0.00060/email
Apply for a 5,000-credit agency trial
New accounts receive 100 free verifications after email confirmation. Agencies may apply for an additional 5,000 credits to evaluate the service properly. Applications are reviewed manually — credits are granted within one business day.
Manual review — no automatic grants. We review each application to prevent abuse. Please use your company email address. Consumer email domains (Gmail, Outlook, etc.) are not eligible.
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Agency FAQ
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