This has been requested in the forums before:
- Setting up email newsletters with your own email server - #17 by EBA
- MailGun is ending their free tier March 1st. Does anyone have good alternatives? - #10 by georgeappiah
A staff member responded curtly:
Ghost newsletter functionality depends on Mailgun. This will not change for the forseeable future. It has nothing to do with restrictions. You cannot just send bulk email newsletters with SMTP. That is not how email newsletters work.
Without further explanation. So far, I’ve been using https://listmonk.app/ successfully, instead.