diff --git a/tests/conftest.py b/tests/conftest.py
index 0d9db39..715c025 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -3,8 +3,6 @@
 from unittest.mock import AsyncMock, patch
 from pathlib import Path
 
-# from asynctest import CoroutineMock, MagicMock, patch
-# import aiohttp
 import json
 import pytest
 from typing import Generator
@@ -20,8 +18,18 @@ def __getitem__(self, name):
 
     def __getattr__(self, name):
         name, ext = name.rsplit("_", 1)
+        parse = False
 
-        return FIXTURES_DIR.joinpath(f"{name}.{ext}").read_text()
+        if ext == "obj":
+            parse = True
+            ext = "json"
+
+        data = FIXTURES_DIR.joinpath(f"{name}.{ext}").read_text()
+
+        if parse:
+            data = json.loads(data)
+
+        return data
 
 
 @pytest.fixture
@@ -68,3 +76,25 @@ def mock_aiohttp_session() -> Generator[dict[str, AsyncMock], None, None]:
         )
 
         yield session
+
+
+@pytest.fixture
+def mock_watersmart_client() -> Generator[AsyncMock, None, None]:
+    """Mock a WaterSmart client."""
+
+    hourly_data = FixtureLoader().realtime_api_response_obj["data"]["series"]
+
+    with (
+        patch(
+            "custom_components.watersmart.client.WaterSmartClient", autospec=True
+        ) as mock_client,
+        patch(
+            "custom_components.watersmart.config_flow.WaterSmartClient",
+            new=mock_client,
+        ),
+    ):
+        client = mock_client.return_value
+        client.async_get_account_number.return_value = "1234567-8900"
+        client.async_get_account_number.async_get_hourly_data = hourly_data
+
+        yield client
diff --git a/tests/test_config_flow.py b/tests/test_config_flow.py
new file mode 100644
index 0000000..af1a8de
--- /dev/null
+++ b/tests/test_config_flow.py
@@ -0,0 +1,154 @@
+"""Test the Simple Integration config flow."""
+
+from unittest.mock import patch
+
+from homeassistant import config_entries, setup
+from homeassistant.core import HomeAssistant
+from custom_components.watersmart.const import DOMAIN
+from custom_components.watersmart.client import AuthenticationError
+
+
+async def test_successful_flow(hass: HomeAssistant, mock_watersmart_client):
+    """Test we get the form."""
+
+    await setup.async_setup_component(hass, "persistent_notification", {})
+    result = await hass.config_entries.flow.async_init(
+        DOMAIN, context={"source": config_entries.SOURCE_USER}
+    )
+    assert result["type"] == "form"
+    assert result["errors"] == {}
+
+    with patch(
+        "custom_components.watersmart.async_setup_entry",
+        return_value=True,
+    ) as mock_setup_entry:
+        configured_result = await hass.config_entries.flow.async_configure(
+            result["flow_id"],
+            {
+                "host": "test",
+                "username": "test@home-assistant.io",
+                "password": "Passw0rd",
+            },
+        )
+
+    assert configured_result["type"] == "create_entry"
+    assert configured_result["title"] == "test (test@home-assistant.io)"
+    assert configured_result["data"] == {
+        "host": "test",
+        "username": "test@home-assistant.io",
+        "password": "Passw0rd",
+    }
+    await hass.async_block_till_done()
+    assert len(mock_setup_entry.mock_calls) == 1
+
+
+async def test_client_timeout(hass: HomeAssistant, mock_watersmart_client):
+    """Test we get the form."""
+
+    mock_watersmart_client.async_get_account_number.side_effect = TimeoutError(
+        "timeout"
+    )
+
+    await setup.async_setup_component(hass, "persistent_notification", {})
+    result = await hass.config_entries.flow.async_init(
+        DOMAIN, context={"source": config_entries.SOURCE_USER}
+    )
+    assert result["type"] == "form"
+    assert result["errors"] == {}
+
+    with patch(
+        "custom_components.watersmart.async_setup_entry",
+        return_value=True,
+    ) as mock_setup_entry:
+        configured_result = await hass.config_entries.flow.async_configure(
+            result["flow_id"],
+            {
+                "host": "test",
+                "username": "test@home-assistant.io",
+                "password": "Passw0rd",
+            },
+        )
+
+    assert "title" not in configured_result
+    assert "data" not in configured_result
+
+    assert configured_result["type"] == "form"
+    assert configured_result["errors"] == {
+        "base": "cannot_connect",
+    }
+    await hass.async_block_till_done()
+    assert len(mock_setup_entry.mock_calls) == 0
+
+
+async def test_auth_error(hass: HomeAssistant, mock_watersmart_client):
+    """Test we get the form."""
+
+    mock_watersmart_client.async_get_account_number.side_effect = AuthenticationError(
+        "invalid credentials"
+    )
+
+    await setup.async_setup_component(hass, "persistent_notification", {})
+    result = await hass.config_entries.flow.async_init(
+        DOMAIN, context={"source": config_entries.SOURCE_USER}
+    )
+    assert result["type"] == "form"
+    assert result["errors"] == {}
+
+    with patch(
+        "custom_components.watersmart.async_setup_entry",
+        return_value=True,
+    ) as mock_setup_entry:
+        configured_result = await hass.config_entries.flow.async_configure(
+            result["flow_id"],
+            {
+                "host": "test",
+                "username": "test@home-assistant.io",
+                "password": "Passw0rd",
+            },
+        )
+
+    assert "title" not in configured_result
+    assert "data" not in configured_result
+
+    assert configured_result["type"] == "form"
+    assert configured_result["errors"] == {
+        "base": "invalid_auth",
+    }
+    await hass.async_block_till_done()
+    assert len(mock_setup_entry.mock_calls) == 0
+
+
+async def test_no_account_number(hass: HomeAssistant, mock_watersmart_client):
+    """Test we get the form."""
+
+    mock_watersmart_client.async_get_account_number.return_value = None
+
+    await setup.async_setup_component(hass, "persistent_notification", {})
+    result = await hass.config_entries.flow.async_init(
+        DOMAIN, context={"source": config_entries.SOURCE_USER}
+    )
+    assert result["type"] == "form"
+    assert result["errors"] == {}
+
+    with patch(
+        "custom_components.watersmart.async_setup_entry",
+        return_value=True,
+    ) as mock_setup_entry:
+        configured_result = await hass.config_entries.flow.async_configure(
+            result["flow_id"],
+            {
+                "host": "test",
+                "username": "test@home-assistant.io",
+                "password": "Passw0rd",
+            },
+        )
+
+    assert "title" not in configured_result
+    assert "data" not in configured_result
+
+    assert configured_result["type"] == "form"
+    assert configured_result["errors"] == {
+        "base": "invalid_auth",
+    }
+    await hass.async_block_till_done()
+    assert len(mock_setup_entry.mock_calls) == 0