diff --git a/doc/guix.texi b/doc/guix.texi
index ab9f17b29f..390c4347d6 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -11827,11 +11827,12 @@ in the definitions of packages.
 
 @item --recursive
 @itemx -r
-This option is deprecated in favor of @option{--serializer}.  It is a
-legacy alias for that with @var{type} set to @code{nar}.
+The @option{--recursive} option is deprecated in favor of
+@option{--serializer=nar} (see below); @option{-r} remains accepted as a
+convenient shorthand.
 
 @item --serializer=@var{type}
-@itemx -S
+@itemx -S @var{type}
 Compute the hash on @var{file} using @var{type} serialization.
 
 @var{type} may be one of the following:
diff --git a/guix/scripts/hash.scm b/guix/scripts/hash.scm
index 9715dc7779..4e792c6a03 100644
--- a/guix/scripts/hash.scm
+++ b/guix/scripts/hash.scm
@@ -1,5 +1,5 @@
 ;;; GNU Guix --- Functional package management for GNU
-;;; Copyright © 2012, 2013, 2014, 2016, 2017, 2020, 2021 Ludovic Courtès <ludo@gnu.org>
+;;; Copyright © 2012-2014, 2016-2017, 2020-2022 Ludovic Courtès <ludo@gnu.org>
 ;;; Copyright © 2013 Nikita Karetnikov <nikita@karetnikov.org>
 ;;; Copyright © 2016 Jan Nieuwenhuizen <janneke@gnu.org>
 ;;; Copyright © 2018 Tim Gesthuizen <tim.gesthuizen@yahoo.de>
@@ -134,8 +134,9 @@ and 'base16' ('hex' and 'hexadecimal' can be used as well).\n"))
                               (alist-delete 'format result))))
         (option '(#\r "recursive") #f #f
                 (lambda (opt name arg result)
-                  (warning (G_ "'--recursive' is deprecated, \
-use '--serializer' instead~%"))
+                  (unless (eqv? name #\r)
+                    (warning (G_ "'--recursive' is deprecated, \
+use '--serializer=nar' instead~%")))
                   (alist-cons 'serializer nar-hash
                               (alist-delete 'serializer result))))
         (option '(#\S "serializer") #t #f