diff --git a/wp-includes/pluggable.php b/wp-includes/pluggable.php
index d108e4a457..b097bca227 100644
--- a/wp-includes/pluggable.php
+++ b/wp-includes/pluggable.php
@@ -649,7 +649,10 @@ if ( !function_exists('wp_set_auth_cookie') ) :
  */
 function wp_set_auth_cookie($user_id, $remember = false, $secure = '') {
 	if ( $remember ) {
-		$expiration = $expire = time() + apply_filters('auth_cookie_expiration', 14 * DAY_IN_SECONDS, $user_id, $remember);
+		$expiration = time() + apply_filters('auth_cookie_expiration', 14 * DAY_IN_SECONDS, $user_id, $remember);
+		// Ensure the browser will continue to send the cookie after the expiration time is reached.
+		// Needed for the login grace period in wp_validate_auth_cookie().
+		$expire = $expiration + ( 12 * HOUR_IN_SECONDS );
 	} else {
 		$expiration = time() + apply_filters('auth_cookie_expiration', 2 * DAY_IN_SECONDS, $user_id, $remember);
 		$expire = 0;