diff --git a/tests/components/oncue/test_config_flow.py b/tests/components/oncue/test_config_flow.py
index 5350270c15b..df9de02a6b3 100644
--- a/tests/components/oncue/test_config_flow.py
+++ b/tests/components/oncue/test_config_flow.py
@@ -7,7 +7,13 @@ from aiooncue import LoginFailedException
 from homeassistant import config_entries
 from homeassistant.components.oncue.const import DOMAIN
 from homeassistant.core import HomeAssistant
-from homeassistant.data_entry_flow import RESULT_TYPE_CREATE_ENTRY, RESULT_TYPE_FORM
+from homeassistant.data_entry_flow import (
+    RESULT_TYPE_ABORT,
+    RESULT_TYPE_CREATE_ENTRY,
+    RESULT_TYPE_FORM,
+)
+
+from tests.common import MockConfigEntry
 
 
 async def test_form(hass: HomeAssistant) -> None:
@@ -104,3 +110,32 @@ async def test_form_unknown_exception(hass: HomeAssistant) -> None:
 
     assert result2["type"] == RESULT_TYPE_FORM
     assert result2["errors"] == {"base": "unknown"}
+
+
+async def test_already_configured(hass: HomeAssistant) -> None:
+    """Test already configured."""
+    entry = MockConfigEntry(
+        domain=DOMAIN,
+        data={
+            "username": "TEST-username",
+            "password": "test-password",
+        },
+        unique_id="test-username",
+    )
+    entry.add_to_hass(hass)
+
+    result = await hass.config_entries.flow.async_init(
+        DOMAIN, context={"source": config_entries.SOURCE_USER}
+    )
+
+    with patch("homeassistant.components.oncue.config_flow.Oncue.async_login"):
+        result2 = await hass.config_entries.flow.async_configure(
+            result["flow_id"],
+            {
+                "username": "test-username",
+                "password": "test-password",
+            },
+        )
+
+    assert result2["type"] == RESULT_TYPE_ABORT
+    assert result2["reason"] == "already_configured"