tributors: kingmailer, chandersbs, krishnamo

King SMTP is a free WordPress SMTP and Email Log plugin. No Pro version, no paywalls — everything is included for free. Connect WordPress to any SMTP provider or use the built-in KingSMTP integration. Every email your site sends gets logged, searchable, and can be resent with one click. What this plugin does:

• Connects to any SMTP provider — Gmail, Outlook, SendGrid, Mailgun, or your own server
• Built-in KingSMTP support — send via HTTP API, works even when port 25 is blocked
• Email Log — every sent email is logged with status, recipient, subject and error details
• Search, filter and resend emails directly from your WordPress dashboard
• Failure Alerts — get an email notification when a delivery fails
• Works with WooCommerce, Gravity Forms, Contact Form 7, WPForms, and any plugin that uses wp_mail
• TLS encrypted delivery

Everything is free. No Pro version. Features like Email Log and Failure Alerts are locked behind a paid upgrade in other plugins. In King SMTP they are included for free. Optional: KingSMTP provider KingSMTP is a transactional email service built and maintained since 2017. It supports both SMTP and HTTP API delivery, so it works even when your hosting provider blocks port 25 (common on shared hosting, DigitalOcean, AWS). Buy SMTP with Bitcoin. No KYC required.

Starting with Kingmailer WordPress SMTP consists of just two steps: installing and setting up the plugin. Kingmailer WordPress SMTP is designed to work with the wp_mail functionality and will relay all emails. INSTALL KINGMAILER WORDPRESS SMTP FROM WITHIN WORDPRESS

1. Visit the plugins page within your dashboard and select ‘Add New’;
2. Search for ‘Kingmailer WordPress SMTP’;
3. Activate Kingmailer WordPress SMTP from your Plugins page;
4. Go to ‘after activation’ below.

INSTALL KINGMAILER WORDPRESS SMTP MANUALLY

1. Upload the ‘kingmailer-smtp’ folder to the /wp-content/plugins/ directory;
2. Activate the Kingmailer WordPress SMTP plugin through the ‘Plugins’ menu in WordPress;
3. Go to ‘after activation’ below.

AFTER ACTIVATION

1. You should see Settings button;
2. Go through the settings page and set up the plugin for your site;
3. You’re done!

0.4.2 (2026-03-25)

• New: From column added to Email Log

0.4.1 (2026-03-24)

• Fix: Prevent failure alert email loop when delivery fails
• Fix: API timeout capped at 10s to prevent PHP execution time crash

0.4.0 (2026-03-23)

• New: Tabbed admin interface (General, Email Log, Alerts, Test Email, Settings)
• New: Email Log — all sent emails logged with status, search, filter, resend and delete
• New: Failure Alerts — email notification when delivery fails
• New: Multi-provider support — SMTP and KingSMTP selectable from General tab
• New: Safe upgrade routine — existing settings are never lost on update
• Improved: Test Email tab with custom recipient input

0.3.15

• Maintenance release 0.3.10 (2022-06-12)
• Tested with new WP version 0.3.09 (2021-07-31)
• Tested with new WP version 0.3.08 (2021-02-06)
• Attachment fix = 0.3.07 (2020-12-12)::
• Remove SMTP functionality = 0.3.0 (2020-11-28):
• Add SMTP functionality

0.2 (2020-11-22):

• Updated text

0.1 (2020-10-17):

• Initial Release