diff --git a/src/wp-includes/ms-functions.php b/src/wp-includes/ms-functions.php
index d17de7ead01da..7cfb403e9e289 100644
--- a/src/wp-includes/ms-functions.php
+++ b/src/wp-includes/ms-functions.php
@@ -941,7 +941,7 @@ function wpmu_signup_blog_notification( $domain, $path, $title, $user_login, $us
 	}
 
 	// Send email with activation link.
-	if ( ! is_subdomain_install() || get_current_network_id() != 1 ) {
+	if ( ! is_subdomain_install() || get_current_network_id() !== 1 ) {
 		$activate_url = network_site_url( "wp-activate.php?key=$key" );
 	} else {
 		$activate_url = "http://{$domain}{$path}wp-activate.php?key=$key"; // @todo Use *_url() API.