WordPress at a glance
filter is not described

wpmu_signup_user_notification_subject filter-hook . WP MU

Filters the subject of the notification email of new user signup.


add_filter( 'wpmu_signup_user_notification_subject', 'filter_function_name_7394', 10, 6 );
function filter_function_name_7394( $subject, $user_login, $user_email, $key, $meta, $meta ){
	// filter...

	return $subject;
Subject of the notification email.
User login name.
User email address.
Activation key created in wpmu_signup_user().
Signup meta data.
Default: empty array


  • Since MU (3.0.0)

Where the hook is called

wp-includes/ms-functions.php 1010-1014
apply_filters( 'wpmu_signup_user_notification_subject',
	/* translators: New user notification email subject. 1: Network name, 2: New user login */
	_x( '[%1$s] Activate %2$s', 'New user notification email subject' ),
	$user_login, $user_email, $key, $meta

Where the hook is used (in WP core)

Does not used.