diff --git a/devel/schemata b/devel/schemata
index ae84a528..01e3a3df 100644
--- a/devel/schemata
+++ b/devel/schemata
@@ -14,7 +14,7 @@ are interleaved. Keys are printed as keywords (symbols preceded by a
 colon), e.g. (:id "123" :time 54321 :from "foobar"). Null is printed as
 nil, true as t and false as nil.
 
-This is version 4 of the structured output format.
+This is version 5 of the structured output format.
 
 Version history
 ---------------
@@ -36,6 +36,10 @@ v4
 - (notmuch 0.29) added message.crypto to identify overall message
   cryptographic state
 
+v5
+- sorting support for notmuch show (no change to actual schema,
+  just new command line argument)
+
 Common non-terminals
 --------------------
 
diff --git a/emacs/notmuch-address.el b/emacs/notmuch-address.el
index f0af6667..9fc13bc5 100644
--- a/emacs/notmuch-address.el
+++ b/emacs/notmuch-address.el
@@ -308,7 +308,7 @@ execution, CALLBACK is called when harvesting finishes."
 			    (and config-query
 				 (format " and (%s)" config-query)))
 		  from-or-to-me-query))
-	 (args `("address" "--format=sexp" "--format-version=4"
+	 (args `("address" "--format=sexp" "--format-version=5"
 		 ,(if sent "--output=recipients" "--output=sender")
 		 "--deduplicate=address"
 		 ,query)))
diff --git a/emacs/notmuch-mua.el b/emacs/notmuch-mua.el
index 17954fb3..f510c043 100644
--- a/emacs/notmuch-mua.el
+++ b/emacs/notmuch-mua.el
@@ -235,7 +235,7 @@ Typically this is added to `notmuch-mua-send-hook'."
 ;;; Mua reply
 
 (defun notmuch-mua-reply (query-string &optional sender reply-all)
-  (let ((args '("reply" "--format=sexp" "--format-version=4"))
+  (let ((args '("reply" "--format=sexp" "--format-version=5"))
 	(process-crypto notmuch-show-process-crypto)
 	reply
 	original)
diff --git a/emacs/notmuch-query.el b/emacs/notmuch-query.el
index d7349b77..5c7f4f8d 100644
--- a/emacs/notmuch-query.el
+++ b/emacs/notmuch-query.el
@@ -31,7 +31,7 @@
 A thread is a forest or list of trees. A tree is a two element
 list where the first element is a message, and the second element
 is a possibly empty forest of replies."
-  (let ((args '("show" "--format=sexp" "--format-version=4")))
+  (let ((args '("show" "--format=sexp" "--format-version=5")))
     (when notmuch-show-process-crypto
       (setq args (append args '("--decrypt=true"))))
     (setq args (append args search-terms))
diff --git a/emacs/notmuch-tree.el b/emacs/notmuch-tree.el
index 01a77b71..2f508128 100644
--- a/emacs/notmuch-tree.el
+++ b/emacs/notmuch-tree.el
@@ -1103,7 +1103,7 @@ the same as for the function notmuch-tree."
     (notmuch-tag-clear-cache)
     (let ((proc (notmuch-start-notmuch
 		 "notmuch-tree" (current-buffer) #'notmuch-tree-process-sentinel
-		 "show" "--body=false" "--format=sexp" "--format-version=4"
+		 "show" "--body=false" "--format=sexp" "--format-version=5"
 		 sort-arg message-arg search-args))
 	  ;; Use a scratch buffer to accumulate partial output.
 	  ;; This buffer will be killed by the sentinel, which
diff --git a/emacs/notmuch.el b/emacs/notmuch.el
index 351334aa..739cb93b 100644
--- a/emacs/notmuch.el
+++ b/emacs/notmuch.el
@@ -1020,7 +1020,7 @@ the configured default sort order."
       (save-excursion
 	(let ((proc (notmuch-start-notmuch
 		     "notmuch-search" buffer #'notmuch-search-process-sentinel
-		     "search" "--format=sexp" "--format-version=4"
+		     "search" "--format=sexp" "--format-version=5"
 		     (if oldest-first
 			 "--sort=oldest-first"
 		       "--sort=newest-first")
diff --git a/notmuch-client.h b/notmuch-client.h
index 8227fea4..8643a63f 100644
--- a/notmuch-client.h
+++ b/notmuch-client.h
@@ -137,7 +137,7 @@ chomp_newline (char *str)
  * this.  New (required) map fields can be added without increasing
  * this.
  */
-#define NOTMUCH_FORMAT_CUR 4
+#define NOTMUCH_FORMAT_CUR 5
 /* The minimum supported structured output format version.  Requests
  * for format versions below this will return an error. */
 #define NOTMUCH_FORMAT_MIN 1
diff --git a/test/T310-emacs.sh b/test/T310-emacs.sh
index 7b70175b..d69d94a3 100755
--- a/test/T310-emacs.sh
+++ b/test/T310-emacs.sh
@@ -1060,7 +1060,7 @@ End of search results.
 YYY/notmuch_fail exited with status 1 (see *Notmuch errors* for more details)
 === ERROR ===
 YYY/notmuch_fail exited with status 1
-command: YYY/notmuch_fail search --format\=sexp --format-version\=4 --sort\=newest-first tag\:inbox
+command: YYY/notmuch_fail search --format\=sexp --format-version\=5 --sort\=newest-first tag\:inbox
 exit status: 1"
 
 test_begin_subtest "Search handles subprocess warnings"
diff --git a/test/T450-emacs-show.sh b/test/T450-emacs-show.sh
index 9d08d2cc..a750cc4d 100755
--- a/test/T450-emacs-show.sh
+++ b/test/T450-emacs-show.sh
@@ -192,7 +192,7 @@ test_expect_equal "$(notmuch_emacs_error_sanitize notmuch_fail OUTPUT MESSAGES E
 This is an error (see *Notmuch errors* for more details)
 === ERROR ===
 This is an error
-command: YYY/notmuch_fail show --format\\=sexp --format-version\\=4 --decrypt\\=true --exclude\\=false \\' \\* \\'
+command: YYY/notmuch_fail show --format\\=sexp --format-version\\=5 --decrypt\\=true --exclude\\=false \\' \\* \\'
 exit status: 1
 stderr:
 This is an error