This document lists all the situations where WordPress sends an email, along with how to filter or disable each email.
This is accurate as of WordPress 4.8, and includes some upcoming changes in WordPress 4.9.
There are a few TODOs left. Please bear with me.
- Comments
- Change of Admin Email
- Change of User Email or Password
- Automatic Updates
- New User
- New Site
- Other
To: Site Admin, plus post author if they can edit comments
From: WordPress <wordpress@host>
Subject: [%s] Please moderate: "%s"
Function: wp_notify_moderator()
Pluggable: Yes
Filters: comment_moderation_subject
comment_moderation_text
comment_moderation_recipients
comment_moderation_headers
Disable: Return false from notify_moderator filter
Remove wp_new_comment_notify_moderator action on comment_post hook
"Email me whenever" on Settings -> Discussion
Overwrite the pluggable function
To: Post author
From: WordPress <wordpress@host>
Subject: [%s] Comment: "%s"
[%s] Pingback: "%s"
[%s] Trackback: "%s"
Function: wp_notify_postauthor()
Pluggable: Yes
Filters: comment_notification_subject
comment_notification_text
comment_notification_recipients
comment_notification_headers
Disable: Return false from notify_post_author filter
Remove wp_new_comment_notify_postauthor action on comment_post hook
Overwrite the pluggable function
See also the hardcoded action added to wp_set_comment_status in wp_set_comment_status()
To: Proposed new email address
From: WordPress <wordpress@host>
Subject: [%s] New Admin Email Address
Function: update_option_new_admin_email()
Pluggable: No
Filters: new_admin_email_content
Disable: Remove action on add_option_new_admin_email and update_option_new_admin_email hooks
To: Old site admin email address
From: WordPress <wordpress@host>
Subject: [%s] Notice of Admin Email Change
Function: wp_site_admin_email_change_notification()
Pluggable: No
Filters: site_admin_email_change_email
Disable: Return false from send_site_admin_email_change_email filter
To: Proposed new email address
From: WordPress <wordpress@host>
Subject: [%s] New Network Admin Email Address
Function: update_network_option_new_admin_email()
Pluggable: No
Filters: new_network_admin_email_content
Disable: Remove action on add_site_option_new_admin_email and update_site_option_new_admin_email hooks
To: Old network admin email address
From: WordPress <wordpress@host>
Subject: [%s] Notice of Network Admin Email Change
Function: wp_network_admin_email_change_notification()
Pluggable: No
Filters: network_admin_email_change_email
Disable: Return false from send_network_admin_email_change_email filter
To: User
From: WordPress <wordpress@host>
Subject: [%s] Password Reset
Function: retrieve_password()
Pluggable: No
Filters: retrieve_password_title
retrieve_password_message
Disable: Not possible
To: Site admin
From: WordPress <wordpress@host>
Subject: [%s] Password Changed
Function: wp_password_change_notification()
Pluggable: Yes
Filters: wp_password_change_notification_email (WordPress 4.9+)
Disable: Remove action on after_password_reset hook
Overwrite the pluggable function
To: Proposed new email address
From: WordPress <wordpress@host>
Subject: [%s] New Email Address
Function: send_confirmation_on_profile_email()
Pluggable: No
Filters: new_user_email_content
Disable: Remove action on personal_options_update hook
To: User
From: WordPress <wordpress@host>
Subject: [%s] Notice of Password Change
Function: wp_update_user()
Pluggable: No
Filters: password_change_email
Disable: Return false from send_password_change_email filter
To: User
From: WordPress <wordpress@host>
Subject: [%s] Notice of Email Change
Function: wp_update_user()
Pluggable: No
Filters: email_change_email
Disable: Return false from send_email_change_email filter
To: Site admin / Network admin
From: WordPress <wordpress@host>
Subject: [%s] Your site has updated to WordPress %s
[%s] WordPress %s is available. Please update!
[%s] URGENT: Your site may be down due to a failed update
Function: WP_Automatic_Updater::send_email()
Pluggable: No
Filters: auto_core_update_email
Disable: Return false from auto_core_update_send_email filter
Return false from send_core_update_notification_email filter
To: Site admin / Network admin
From: WordPress <wordpress@host>
Subject: [%s] There were failures during background updates
[%s] Background updates have finished
Function: WP_Automatic_Updater::send_debug_email()
Pluggable: No
Filters: automatic_updates_debug_email
Disable: Return false from automatic_updates_send_debug_email filter
To: User being invited
From: WordPress <wordpress@host>
Subject: [%s] Joining confirmation
Function: wp-admin/user-new.php
Pluggable: No
Filters: None
Disable: Click the "Skip Confirmation Email" checkbox when adding the user
To: User being invited
From: [Network Name] <[network admin]>
Subject: [%s] Activate %s
Function: wpmu_signup_user_notification()
Pluggable: No
Filters: wpmu_signup_user_notification_subject
wpmu_signup_user_notification_email
Disable: Click the "Skip Confirmation Email" checkbox when adding the user
Return false from wpmu_signup_user_notification filter
To: Network Admin
From: WordPress <wordpress@host>
Subject: New User Registration: %s
Function: newuser_notify_siteadmin()
Pluggable: No
Filters: newuser_notify_siteadmin
Disable: Filter registrationnotification option value
Remove action on wpmu_new_user hook
Toggle "Registration notification" in Network Admin -> Settings
To: User being added
From: [Network Name] <[network admin]>
Subject: New %s User: %s
Function: wpmu_welcome_user_notification()
Pluggable: No
Filters: update_welcome_user_subject
update_welcome_user_email
See also "Welcome User Email" setting in Network Admin -> Settings
Disable: Click the "Skip Confirmation Email" checkbox when adding the user
Return false from wpmu_welcome_user_notification filter
Remove action on wpmu_activate_user hook
When a new user is created, two emails are sent from the same function. One to the site admin:
To: Site Admin
From: WordPress <wordpress@host>
Subject: [%s] New User Registration
and one to the newly created user:
To: User being added
From: WordPress <wordpress@host>
Subject: [%s] Your username and password info
Details:
Function: wp_new_user_notification()
Pluggable: Yes
Filters: wp_new_user_notification_email_admin (WordPress 4.9+)
wp_new_user_notification_email (WordPress 4.9+)
Disable: Remove wp_send_new_user_notifications action on register_new_user hook
Remove wp_send_new_user_notifications action on edit_user_created_user hook
Remove wp_send_new_user_notifications action on network_site_new_created_user hook
Remove wp_send_new_user_notifications action on network_site_users_created_user hook
Remove wp_send_new_user_notifications action on network_user_new_created_user hook
Overwrite the pluggable function
To: Site Admin
From: WordPress <wordpress@host>
Subject: New WordPress Site
Function: wp_new_blog_notification()
Pluggable: Yes
Filters: None
Disable: Overwrite the pluggable function
To: Network Admin
From: Site Admin <[network admin]>
Subject: [%s] New Site Created
Function: wp-admin/network/site-new.php
Pluggable: No
Filters: None
Disable: Not possible
To: Site Admin
From: [Network Name] <[network admin]>
Subject: [%s] Activate %s
Function: wpmu_signup_blog_notification()
Pluggable: No
Filters: wpmu_signup_blog_notification_subject
wpmu_signup_blog_notification_email
Disable: Return false from wpmu_signup_blog_notification filter
Remove action on after_signup_site hook
To: Network Admin
From: WordPress <wordpress@host>
Subject: New Site Registration: %s
Function: newblog_notify_siteadmin()
Pluggable: No
Filters: newblog_notify_siteadmin
Disable: Filter registrationnotification option value
Remove action on wpmu_new_blog hook
Toggle "Registration notification" in Network Admin -> Settings
To: Site Admin
From: [Network Name] <[network admin]>
Subject: New %s Site: %s
Function: wpmu_welcome_notification()
Pluggable: No
Filters: update_welcome_subject
update_welcome_email
See also "Welcome Email" setting in Network Admin -> Settings
Disable: Return false from wpmu_welcome_notification filter
Remove action on wpmu_activate_blog hook
To: Site Admin
From: WordPress <wordpress@host>
Subject: [ %s ] Delete My Site
Function: wp-admin/ms-delete-site.php
Pluggable: No
Filters: delete_site_email_content
Disable: Not possible