Automatically Suppress Contacts Based on ISP or Group Domains in Mautic

I’m looking for a way to automatically detect group domains (like Gmail, Yahoo, Outlook, etc.) when a contact is added to Mautic, and then move those contacts to the suppression list instead of allowing them to receive campaign emails.

My goal:

  • When a new contact is added (via API or any method),
  • If their email belongs to an ISP domain (like @gmail.com, @yahoo.com, etc.),
  • They should be suppressed automatically (added to the Do Not Contact list or an equivalent suppression mechanism),
  • I do not want to manually assign them to a suppression segment or manually set the DNC flag.

What I’m looking for:

  • A way to implement this logic using Mautic’s core features, plugins, or events.
  • Any examples (campaign, automation, or PHP plugin code) that can help trigger suppression based on domain.
  • Advice from anyone who has handled ISP-based filtering or suppression in Mautic.

Thanks in advance for any suggestions or solutions!