Gain fast visibility into risky signups. When a new contact is created in Mautic, the flow checks the email and sends a warning to Slack if the address looks unsafe. Marketing and sales teams can act early, keep lists clean, and protect sender reputation.

Here is how it works. An event in Mautic fires when a contact is identified. A quick check ensures only new contacts move forward. The contact details are extracted, and One Simple API tests the email for deliverability, domain validity, and disposable status. If any check fails, a clear alert with the contact name and email is posted to a Slack channel so the team can review or block the lead.

Setup is simple with Mautic, One Simple API, and Slack credentials. You get fewer bounced emails, less manual review, and faster response to suspicious leads. This is useful for lead capture forms, newsletter signups, and event lists where email quality matters most.

• Real time trigger on new contact identified in Mautic
• Filter ensures only new contact events continue through the checks
• Extracts key contact fields like name and email for validation
• Validates email with One Simple API for deliverability, domain, and disposable status
• Flexible any match rule flags a risk if any check fails
• Sends a formatted Slack alert with contact details to a chosen channel

• Reduce manual email checks from hours to minutes
• Improve data quality by stopping risky emails before nurture
• Lower bounce rates and protect sender reputation
• Connect Mautic, One Simple API, and Slack in one flow
• Handle more signups without adding review workload

1. Import the template into n8n: Create a new workflow in n8n > Click the three dots menu > Select 'Import from File' > Choose the downloaded JSON file.
2. You'll need accounts with Mautic, One Simple API and Slack. See the Tools Required section above for links to create accounts with these services.
3. Open the Mautic trigger node. In the Credential to connect with menu, click Create new credential, select OAuth2, and follow the on screen steps to connect your Mautic account. Verify the base URL and finish the authorization.
4. In the same Mautic node, confirm the event is set to contact identified and includes the new contact event. Save the node.
5. Open the email validation node. In the Credential drop down, choose Create new credential for One Simple API, then paste your API key from the One Simple API dashboard. Save the credential.
6. Check the email field mapping in the validation node. It should point to the Mautic contact email field so the correct address is tested.
7. Open the Slack node. Click Create new credential, then authorize Slack or paste a valid Slack access token. Select the target channel where alerts should post.
8. Review the risk logic in the IF node. It flags an alert when deliverability is not good, the domain is invalid, or the email is disposable. Keep combine operation set to any.
9. Run a test by creating a new contact in Mautic with a disposable or invalid email. Check the n8n execution log and confirm the Slack channel receives the alert.
10. If no alert appears, verify the Mautic trigger event is firing, confirm One Simple API quota is available, and check that the Slack token has permission to post to the selected channel.
11. Turn the workflow on in n8n. Monitor the Slack channel for the first week and adjust the alert text or channel as needed.