WordPress at a glance
filter is not described

wpmu_signup_blog_notification_subject filter-hook . WP MU

Filters the subject of the new blog notification email.


add_filter( 'wpmu_signup_blog_notification_subject', 'filter_function_name_1690', 10, 9 );
function filter_function_name_1690( $subject, $domain, $path, $title, $user_login, $user_email, $key, $meta, $meta ){
	// filter...

	return $subject;
Subject of the notification email.
Site domain.
Site path.
Site title.
User login name.
User email address.
Activation key created in wpmu_signup_blog().
Signup meta data. By default, contains the requested privacy setting and lang_id.


  • Since MU (3.0.0)

Where the hook is called

wp-includes/ms-functions.php 915-919
apply_filters( 'wpmu_signup_blog_notification_subject',
	/* translators: New site notification email subject. 1: Network name, 2: New site URL */
	_x( '[%1$s] Activate %2$s', 'New site notification email subject' ),
	$domain, $path, $title, $user_login, $user_email, $key, $meta

Where the hook is used (in WP core)

Does not used.