diff --git a/Documentation/git-branch.txt b/Documentation/git-branch.txt
index cfceac56d..6410c3d34 100644
--- a/Documentation/git-branch.txt
+++ b/Documentation/git-branch.txt
@@ -163,8 +163,9 @@ start-point is either a local or remote-tracking branch.
 	Open an editor and edit the text to explain what the branch is
 	for, to be used by various other commands (e.g. `request-pull`).
 
---contains <commit>::
-	Only list branches which contain the specified commit.
+--contains [<commit>]::
+	Only list branches which contain the specified commit (HEAD
+	if not specified).
 
 --merged [<commit>]::
 	Only list branches whose tips are reachable from the