diff --git a/test/T350-crypto.sh b/test/T350-crypto.sh
index 7dab39a2..1d408af7 100755
--- a/test/T350-crypto.sh
+++ b/test/T350-crypto.sh
@@ -394,7 +394,7 @@ test_expect_equal_json \
 
 test_begin_subtest "reply to encrypted message"
 output=$(notmuch reply --decrypt subject:"test encrypted message 002" \
-    | grep -v -e '^In-Reply-To:' -e '^References:')
+    | notmuch_drop_mail_headers In-Reply-To References)
 expected='From: Notmuch Test Suite <test_suite@notmuchmail.org>
 Subject: Re: test encrypted message 002
 
diff --git a/test/test-lib.sh b/test/test-lib.sh
index d2b2a47f..09ee815d 100644
--- a/test/test-lib.sh
+++ b/test/test-lib.sh
@@ -507,6 +507,16 @@ NOTMUCH_DUMP_TAGS ()
     notmuch dump --include=tags "${@}" | sed '/^#/d' | sort
 }
 
+notmuch_drop_mail_headers ()
+{
+    $NOTMUCH_PYTHON -c "
+import email,sys
+msg=email.message_from_file(sys.stdin)
+for hdr in sys.argv[1:]: del msg[hdr]
+print(msg.as_string(False))
+" $*
+}
+
 notmuch_search_sanitize ()
 {
     perl -pe 's/("?thread"?: ?)("?)................("?)/\1\2XXX\3/'