diff --git a/homeassistant/components/nut/config_flow.py b/homeassistant/components/nut/config_flow.py
index 04889bb3f3f..0721ea10f94 100644
--- a/homeassistant/components/nut/config_flow.py
+++ b/homeassistant/components/nut/config_flow.py
@@ -99,7 +99,9 @@ class ConfigFlow(config_entries.ConfigFlow, domain=DOMAIN):
     def _host_port_alias_already_configured(self, host, port, alias):
         """See if we already have a nut entry matching user input configured."""
         existing_host_port_aliases = {
-            _format_host_port_alias(host, port, alias)
+            _format_host_port_alias(
+                entry.data[CONF_HOST], entry.data[CONF_PORT], entry.data.get(CONF_ALIAS)
+            )
             for entry in self._async_current_entries()
         }
         return _format_host_port_alias(host, port, alias) in existing_host_port_aliases
diff --git a/tests/components/nut/test_config_flow.py b/tests/components/nut/test_config_flow.py
index 362f6c0b2ba..2ffc470ccf0 100644
--- a/tests/components/nut/test_config_flow.py
+++ b/tests/components/nut/test_config_flow.py
@@ -4,6 +4,8 @@ from asynctest import MagicMock, patch
 from homeassistant import config_entries, setup
 from homeassistant.components.nut.const import DOMAIN
 
+from tests.common import MockConfigEntry
+
 
 def _get_mock_pynutclient(list_vars=None):
     pynutclient = MagicMock()
@@ -62,6 +64,12 @@ async def test_form_import(hass):
     """Test we get the form with import source."""
     await setup.async_setup_component(hass, "persistent_notification", {})
 
+    config_entry = MockConfigEntry(
+        domain=DOMAIN,
+        data={"host": "2.2.2.2", "port": 123, "resources": ["battery.charge"]},
+    )
+    config_entry.add_to_hass(hass)
+
     mock_pynut = _get_mock_pynutclient(list_vars={"battery.voltage": "serial"})
 
     with patch(
@@ -92,7 +100,7 @@ async def test_form_import(hass):
     }
     await hass.async_block_till_done()
     assert len(mock_setup.mock_calls) == 1
-    assert len(mock_setup_entry.mock_calls) == 1
+    assert len(mock_setup_entry.mock_calls) == 2
 
 
 async def test_form_cannot_connect(hass):