diff --git a/ref-filter.c b/ref-filter.c
index 8447cb09be..f6200196a3 100644
--- a/ref-filter.c
+++ b/ref-filter.c
@@ -342,9 +342,11 @@ static int contents_atom_parser(const struct ref_format *format, struct used_ato
 		atom->u.contents.option = C_SIG;
 	else if (!strcmp(arg, "subject"))
 		atom->u.contents.option = C_SUB;
-	else if (skip_prefix(arg, "trailers", &arg)) {
-		skip_prefix(arg, ":", &arg);
-		if (trailers_atom_parser(format, atom, *arg ? arg : NULL, err))
+	else if (!strcmp(arg, "trailers")) {
+		if (trailers_atom_parser(format, atom, NULL, err))
+			return -1;
+	} else if (skip_prefix(arg, "trailers:", &arg)) {
+		if (trailers_atom_parser(format, atom, arg, err))
 			return -1;
 	} else if (skip_prefix(arg, "lines=", &arg)) {
 		atom->u.contents.option = C_LINES;
diff --git a/t/t6300-for-each-ref.sh b/t/t6300-for-each-ref.sh
index 5ee08cf514..ff7313e9c3 100755
--- a/t/t6300-for-each-ref.sh
+++ b/t/t6300-for-each-ref.sh
@@ -785,6 +785,14 @@ test_expect_success '%(trailers) rejects unknown trailers arguments' '
 	test_i18ncmp expect actual
 '
 
+test_expect_success 'if arguments, %(contents:trailers) shows error if colon is missing' '
+	cat >expect <<-EOF &&
+	fatal: unrecognized %(contents) argument: trailersonly
+	EOF
+	test_must_fail git for-each-ref --format="%(contents:trailersonly)" 2>actual &&
+	test_i18ncmp expect actual
+'
+
 test_expect_success 'basic atom: head contents:trailers' '
 	git for-each-ref --format="%(contents:trailers)" refs/heads/master >actual &&
 	sanitize_pgp <actual >actual.clean &&