diff --git a/help.c b/help.c
index 5583f6cded..602d9fa201 100644
--- a/help.c
+++ b/help.c
@@ -761,12 +761,12 @@ static int append_similar_ref(const char *refname, const struct object_id *oid,
 {
 	struct similar_ref_cb *cb = (struct similar_ref_cb *)(cb_data);
 	char *branch = strrchr(refname, '/') + 1;
-	const char *remote;
 
 	/* A remote branch of the same name is deemed similar */
-	if (skip_prefix(refname, "refs/remotes/", &remote) &&
+	if (starts_with(refname, "refs/remotes/") &&
 	    !strcmp(branch, cb->base_ref))
-		string_list_append(cb->similar_refs, remote);
+		string_list_append_nodup(cb->similar_refs,
+					 shorten_unambiguous_ref(refname, 1));
 	return 0;
 }
 
diff --git a/t/t7600-merge.sh b/t/t7600-merge.sh
index 592850cef7..36b2c8c91f 100755
--- a/t/t7600-merge.sh
+++ b/t/t7600-merge.sh
@@ -836,4 +836,10 @@ test_expect_success 'merge suggests matching remote refname' '
 	grep origin/not-local stderr
 '
 
+test_expect_success 'suggested names are not ambiguous' '
+	git update-ref refs/heads/origin/not-local HEAD &&
+	test_must_fail git merge not-local 2>stderr &&
+	grep remotes/origin/not-local stderr
+'
+
 test_done