diff --git a/docs/howto/custom-file-storage.txt b/docs/howto/custom-file-storage.txt
index d9e18a6003..ed6e610663 100644
--- a/docs/howto/custom-file-storage.txt
+++ b/docs/howto/custom-file-storage.txt
@@ -99,6 +99,8 @@ and underscores from the original filename, removing everything else.
 
 .. method:: get_alternative_name(file_root, file_ext)
 
+.. versionadded:: 3.0
+
 Returns an alternative filename based on the ``file_root`` and ``file_ext``
 parameters. By default, an underscore plus a random 7 character alphanumeric
 string is appended to the filename before the extension.
diff --git a/docs/ref/files/storage.txt b/docs/ref/files/storage.txt
index 0724a0cda1..b2710062df 100644
--- a/docs/ref/files/storage.txt
+++ b/docs/ref/files/storage.txt
@@ -107,6 +107,8 @@ The ``Storage`` class
 
     .. method:: get_alternative_name(file_root, file_ext)
 
+        .. versionadded:: 3.0
+
         Returns an alternative filename based on the ``file_root`` and
         ``file_ext`` parameters, an underscore plus a random 7 character
         alphanumeric string is appended to the filename before the extension.