diff --git a/intl/Makefile b/intl/Makefile
index d7223256eb..a6dd138dad 100644
--- a/intl/Makefile
+++ b/intl/Makefile
@@ -32,7 +32,10 @@ test-srcs := tst-gettext tst-translit tst-gettext2 tst-codeset tst-gettext3
 ifeq ($(have-thread-library),yes)
 test-srcs += $(multithread-test-srcs)
 endif
-tests = tst-ngettext
+tests = \
+  tst-gettext-c-utf8 \
+  tst-ngettext \
+  # tests
 
 before-compile += $(objpfx)msgs.h
 
@@ -117,6 +120,7 @@ $(objpfx)tst-gettext3.out: $(gen-locales)
 $(objpfx)tst-gettext4.out: $(gen-locales)
 $(objpfx)tst-gettext5.out: $(gen-locales)
 $(objpfx)tst-gettext6.out: $(gen-locales)
+$(objpfx)tst-gettext-c-utf8.out: $(gen-locales)
 $(objpfx)tst-translit.out: $(gen-locales)
 endif
 
diff --git a/intl/tst-gettext-c-utf8.c b/intl/tst-gettext-c-utf8.c
new file mode 100644
index 0000000000..bdb9b5396c
--- /dev/null
+++ b/intl/tst-gettext-c-utf8.c
@@ -0,0 +1,37 @@
+/* Check that C.UTF-8 uses C translations (bug 16621).
+   Copyright (C) 2021-2023 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#include <errno.h>
+#include <stdlib.h>
+#include <string.h>
+#include <support/check.h>
+#include <support/support.h>
+
+static int
+do_test (void)
+{
+  if (setenv ("LANGUAGE", "de_DE.UTF-8", 1) != 0)
+    FAIL_EXIT1 ("setenv");
+  if (setenv ("LC_ALL", "C.UTF-8", 1) != 0)
+    FAIL_EXIT1 ("setenv");
+  xsetlocale (LC_ALL, "");
+  TEST_COMPARE_STRING (strerror (ENOENT), "No such file or directory");
+  return 0;
+}
+
+#include <support/test-driver.c>