WordPress wp_mail is the option that needs no setup at all. The Mailer simply hands the email to WordPress, and WordPress hands it to whatever is already configured on your site.
What that actually means:
- If you have an SMTP plugin installed, your email goes out through that service.
- If you do not, it goes out through your web server's own mail program.
The second case is the problem. A web server sending its own email has no reputation worth having, no DKIM signature, and often no matching SPF record. Gmail, Outlook and Yahoo treat it with suspicion, so mail lands in spam or is dropped silently. Many hosts also cap how much you can send, or block bulk mail entirely, without telling you.
When wp_mail is the right choice:
- Sending yourself a test while you set the plugin up
- Occasional site emails, such as a password reset, from a site with no list
When it is the wrong choice:
- Any broadcast to a real list, at any size
How to use it:
- In Delivery, then Sending, add a connection and choose WordPress wp_mail.
- Save, then send yourself a test.
- Check where it arrived. If it landed in spam, that is your answer about what would happen to a broadcast.
Before you mail a real list, add one of the other connections on this screen. Amazon SES is the cheapest at volume, SMTP2GO or Postmark are the easiest to live with, and any SMTP server you already pay for works through the custom SMTP option.
One more thing worth knowing: wp_mail never takes part in connection rotation, and the Mailer will not use it to absorb a send that other connections have paused. It stays exactly where you put it.