PHP Mail

PHP mail()

Server's built-in mail program (sendmail / postfix). No SMTP credentials. Lower deliverability — only choose this if your server is configured for outbound mail.

Easy~1 minServer-sideLow deliverability

When PHP Mail makes sense (rarely)

The PHP option is the original "default" WordPress mailer that this plugin exists to replace. Use it only if:

• Your host has a properly-configured local MTA (sendmail / postfix) with reputable IP and DKIM signing.
• You need a connection that works with zero credentials (e.g. dev environments).
• You're using SendGrail just for tracking + logging without changing the send path.

For real production sends to external domains, use a dedicated SMTP/API provider instead. PHP mail() typically lands in spam.

What it does

When you save a "PHP" connection and an email is routed through it, SendGrail hands the message to WordPress's stock wp_mail() with our pre_wp_mail filter detached. WordPress's PHPMailer is configured with no SMTP host, so it falls through to PHP's built-in mail() function, which talks to the OS-level mail program (sendmail / postfix / qmail / Exim).

Step-by-step

Add the connection

SendGrail → Connections → Add Connection → pick PHP from the provider grid.

Fill in the form

Only three fields are visible (no host, port, credentials — there are none):

• Connection Name: PHP Mail
• From Email: the address sendmail will use as From: header
• From Name: display name

Click Save.

Test

SendGrail → Test Email → pick PHP → send to your inbox.

If it lands → your server's local mail works. If it doesn't (after 5 min) → your server has no working MTA. Use a different provider.

Troubleshooting

Test email succeeds in plugin but never arrives

wp_mail() returns true if the OS accepts the message — but the OS may then drop it silently (no MX records, blacklisted IP, sendmail not configured). Check the server's mail queue (mailq on Unix-like systems) or local mail log (/var/log/mail.log). If the message disappears immediately with no error, the local mail program isn't configured to actually deliver.

Lands in recipient's spam folder

Almost guaranteed without proper setup. PHP mail() doesn't sign messages with DKIM, doesn't use SPF, and the sending IP is usually shared with thousands of WordPress installs. Switch to a dedicated provider — every other connection type in SendGrail will deliver better than this.

mail() has been disabled for security reasons

Your host disabled PHP's mail() function. Common on managed hosts (GoDaddy, some shared hosts). Use any SMTP/API provider instead — they all bypass mail().

What's next

• Other SMTP — slightly better than PHP mail(). Use your host's SMTP server with auth.
• Pick a real provider — for any production WordPress site, use SendGrid / Mailgun / Postmark / SES instead.