diff --git a/homeassistant/components/airvisual_pro/config_flow.py b/homeassistant/components/airvisual_pro/config_flow.py
index 7cf03009932..23da39150c5 100644
--- a/homeassistant/components/airvisual_pro/config_flow.py
+++ b/homeassistant/components/airvisual_pro/config_flow.py
@@ -2,6 +2,7 @@
 from __future__ import annotations
 
 from collections.abc import Mapping
+from dataclasses import dataclass, field
 from typing import Any
 
 from pyairvisual.node import (
@@ -33,13 +34,24 @@ STEP_USER_SCHEMA = vol.Schema(
 )
 
 
-async def async_validate_credentials(ip_address: str, password: str) -> dict[str, Any]:
-    """Validate an IP address/password combo (and return any errors as appropriate)."""
+@dataclass
+class ValidationResult:
+    """Define a validation result."""
+
+    serial_number: str | None = None
+    errors: dict[str, Any] = field(default_factory=dict)
+
+
+async def async_validate_credentials(
+    ip_address: str, password: str
+) -> ValidationResult:
+    """Validate an IP address/password combo."""
     node = NodeSamba(ip_address, password)
     errors = {}
 
     try:
         await node.async_connect()
+        measurements = await node.async_get_latest_measurements()
     except InvalidAuthenticationError as err:
         LOGGER.error("Invalid password for Pro at IP address %s: %s", ip_address, err)
         errors["base"] = "invalid_auth"
@@ -52,10 +64,12 @@ async def async_validate_credentials(ip_address: str, password: str) -> dict[str
     except Exception as err:  # pylint: disable=broad-except
         LOGGER.exception("Unknown error while connecting to %s: %s", ip_address, err)
         errors["base"] = "unknown"
+    else:
+        return ValidationResult(serial_number=measurements["serial_number"])
     finally:
         await node.async_disconnect()
 
-    return errors
+    return ValidationResult(errors=errors)
 
 
 class AirVisualProFlowHandler(config_entries.ConfigFlow, domain=DOMAIN):
@@ -89,11 +103,15 @@ class AirVisualProFlowHandler(config_entries.ConfigFlow, domain=DOMAIN):
 
         assert self._reauth_entry
 
-        if errors := await async_validate_credentials(
+        validation_result = await async_validate_credentials(
             self._reauth_entry.data[CONF_IP_ADDRESS], user_input[CONF_PASSWORD]
-        ):
+        )
+
+        if validation_result.errors:
             return self.async_show_form(
-                step_id="reauth_confirm", data_schema=STEP_REAUTH_SCHEMA, errors=errors
+                step_id="reauth_confirm",
+                data_schema=STEP_REAUTH_SCHEMA,
+                errors=validation_result.errors,
             )
 
         self.hass.config_entries.async_update_entry(
@@ -113,14 +131,18 @@ class AirVisualProFlowHandler(config_entries.ConfigFlow, domain=DOMAIN):
 
         ip_address = user_input[CONF_IP_ADDRESS]
 
-        await self.async_set_unique_id(ip_address)
-        self._abort_if_unique_id_configured()
-
-        if errors := await async_validate_credentials(
+        validation_result = await async_validate_credentials(
             ip_address, user_input[CONF_PASSWORD]
-        ):
+        )
+
+        if validation_result.errors:
             return self.async_show_form(
-                step_id="user", data_schema=STEP_USER_SCHEMA, errors=errors
+                step_id="user",
+                data_schema=STEP_USER_SCHEMA,
+                errors=validation_result.errors,
             )
 
+        await self.async_set_unique_id(validation_result.serial_number)
+        self._abort_if_unique_id_configured()
+
         return self.async_create_entry(title=ip_address, data=user_input)
diff --git a/tests/components/airvisual_pro/conftest.py b/tests/components/airvisual_pro/conftest.py
index c5851e940de..5846a988688 100644
--- a/tests/components/airvisual_pro/conftest.py
+++ b/tests/components/airvisual_pro/conftest.py
@@ -12,9 +12,9 @@ from tests.common import MockConfigEntry, load_fixture
 
 
 @pytest.fixture(name="config_entry")
-def config_entry_fixture(hass, config, unique_id):
+def config_entry_fixture(hass, config):
     """Define a config entry fixture."""
-    entry = MockConfigEntry(domain=DOMAIN, unique_id=unique_id, data=config)
+    entry = MockConfigEntry(domain=DOMAIN, unique_id="XXXXXXX", data=config)
     entry.add_to_hass(hass)
     return entry
 
@@ -69,9 +69,3 @@ async def setup_airvisual_pro_fixture(hass, config, pro):
         assert await async_setup_component(hass, DOMAIN, config)
         await hass.async_block_till_done()
         yield
-
-
-@pytest.fixture(name="unique_id")
-def unique_id_fixture(hass):
-    """Define a config entry unique ID fixture."""
-    return "192.168.1.101"
diff --git a/tests/components/airvisual_pro/test_config_flow.py b/tests/components/airvisual_pro/test_config_flow.py
index 32c4e14ba76..61cd43f058d 100644
--- a/tests/components/airvisual_pro/test_config_flow.py
+++ b/tests/components/airvisual_pro/test_config_flow.py
@@ -52,10 +52,16 @@ async def test_create_entry(
     }
 
 
-async def test_duplicate_error(hass, config, config_entry):
+async def test_duplicate_error(hass, config, config_entry, setup_airvisual_pro):
     """Test that errors are shown when duplicates are added."""
     result = await hass.config_entries.flow.async_init(
-        DOMAIN, context={"source": SOURCE_USER}, data=config
+        DOMAIN, context={"source": SOURCE_USER}
+    )
+    assert result["type"] == data_entry_flow.FlowResultType.FORM
+    assert result["step_id"] == "user"
+
+    result = await hass.config_entries.flow.async_configure(
+        result["flow_id"], user_input=config
     )
     assert result["type"] == data_entry_flow.FlowResultType.ABORT
     assert result["reason"] == "already_configured"
diff --git a/tests/components/airvisual_pro/test_diagnostics.py b/tests/components/airvisual_pro/test_diagnostics.py
index ab780b90704..5847dd7ed88 100644
--- a/tests/components/airvisual_pro/test_diagnostics.py
+++ b/tests/components/airvisual_pro/test_diagnostics.py
@@ -17,7 +17,7 @@ async def test_entry_diagnostics(hass, config_entry, hass_client, setup_airvisua
             "pref_disable_new_entities": False,
             "pref_disable_polling": False,
             "source": "user",
-            "unique_id": "192.168.1.101",
+            "unique_id": "XXXXXXX",
             "disabled_by": None,
         },
         "data": {