diff --git a/man/man1/notmuch-reply.1 b/man/man1/notmuch-reply.1
index deb3ae1d..ec8da1f7 100644
--- a/man/man1/notmuch-reply.1
+++ b/man/man1/notmuch-reply.1
@@ -37,12 +37,17 @@ Supported options for
 include
 .RS
 .TP 4
-.BR \-\-format= ( default | headers\-only )
+.BR \-\-format= ( default | json | headers\-only )
 .RS
 .TP 4
 .BR default
 Includes subject and quoted message body.
 .TP
+.BR json
+Produces JSON output containing headers for a reply message and the
+contents of the original message. This output can be used by a client
+to create a reply message intelligently.
+.TP
 .BR headers\-only
 Only produces In\-Reply\-To, References, To, Cc, and Bcc headers.
 .RE
@@ -73,7 +78,8 @@ with a search string matching a single message, (such as
 id:<message-id>), but it can be useful to reply to several messages at
 once. For example, when a series of patches are sent in a single
 thread, replying to the entire thread allows for the reply to comment
-on issue found in multiple patches.
+on issues found in multiple patches. The default format supports
+replying to multiple messages at once, but the JSON format does not.
 .RE
 .RE