diff --git a/core/modules/node/src/NodeInterface.php b/core/modules/node/src/NodeInterface.php
index d762e3a3a1af6f19f2cc6c11a80fcd3e55776e72..89d9d114c6a279d18dc69dbc363c62fff47737b3 100644
--- a/core/modules/node/src/NodeInterface.php
+++ b/core/modules/node/src/NodeInterface.php
@@ -54,8 +54,9 @@ public function getType();
   /**
    * Gets the node title.
    *
-   * @return string
-   *   Title of the node.
+   * @return string|null
+   *   Title of the node, or NULL if the node doesn't yet have a title (for
+   *   example, if a new node is being previewed).
    */
   public function getTitle();