diff --git a/wp-includes/author-template.php b/wp-includes/author-template.php
index ebdc9a4bdb..e7b981be48 100644
--- a/wp-includes/author-template.php
+++ b/wp-includes/author-template.php
@@ -234,7 +234,7 @@ function get_author_posts_url($author_id, $author_nicename = '') {
 				$author_nicename = $user->user_nicename;
 		}
 		$link = str_replace('%author%', $author_nicename, $link);
-		$link = home_url() . trailingslashit($link);
+		$link = home_url( user_trailingslashit( $link ) );
 	}
 
 	$link = apply_filters('author_link', $link, $author_id, $author_nicename);