diff --git a/homeassistant/components/smappee/__init__.py b/homeassistant/components/smappee/__init__.py
index 7fa30965aa8..372441ec586 100644
--- a/homeassistant/components/smappee/__init__.py
+++ b/homeassistant/components/smappee/__init__.py
@@ -11,6 +11,7 @@ from homeassistant.const import (
     CONF_PLATFORM,
 )
 from homeassistant.core import HomeAssistant
+from homeassistant.exceptions import ConfigEntryNotReady
 from homeassistant.helpers import config_entry_oauth2_flow, config_validation as cv
 from homeassistant.helpers.typing import ConfigType
 from homeassistant.util import Throttle
@@ -94,11 +95,17 @@ async def async_setup_entry(hass: HomeAssistant, entry: SmappeeConfigEntry) -> b
             )
         await hass.async_add_executor_job(smappee.load_local_service_location)
     else:
-        implementation = (
-            await config_entry_oauth2_flow.async_get_config_entry_implementation(
-                hass, entry
+        try:
+            implementation = (
+                await config_entry_oauth2_flow.async_get_config_entry_implementation(
+                    hass, entry
+                )
             )
-        )
+        except config_entry_oauth2_flow.ImplementationUnavailableError as err:
+            raise ConfigEntryNotReady(
+                translation_domain=DOMAIN,
+                translation_key="oauth2_implementation_unavailable",
+            ) from err
 
         smappee_api = api.ConfigEntrySmappeeApi(hass, entry, implementation)
 
diff --git a/homeassistant/components/smappee/strings.json b/homeassistant/components/smappee/strings.json
index d1f333ffcdc..0df1c68ecba 100644
--- a/homeassistant/components/smappee/strings.json
+++ b/homeassistant/components/smappee/strings.json
@@ -43,5 +43,10 @@
         "title": "Discovered Smappee device"
       }
     }
+  },
+  "exceptions": {
+    "oauth2_implementation_unavailable": {
+      "message": "[%key:common::exceptions::oauth2_implementation_unavailable::message%]"
+    }
   }
 }
diff --git a/tests/components/smappee/test_init.py b/tests/components/smappee/test_init.py
index cc752964a27..b419662d0fc 100644
--- a/tests/components/smappee/test_init.py
+++ b/tests/components/smappee/test_init.py
@@ -3,8 +3,11 @@
 from unittest.mock import patch
 
 from homeassistant.components.smappee.const import DOMAIN
-from homeassistant.config_entries import SOURCE_ZEROCONF
+from homeassistant.config_entries import SOURCE_USER, SOURCE_ZEROCONF, ConfigEntryState
 from homeassistant.core import HomeAssistant
+from homeassistant.helpers.config_entry_oauth2_flow import (
+    ImplementationUnavailableError,
+)
 
 from tests.common import MockConfigEntry
 
@@ -38,3 +41,31 @@ async def test_unload_config_entry(hass: HomeAssistant) -> None:
         await hass.config_entries.async_unload(entry.entry_id)
         await hass.async_block_till_done()
         assert not hass.data.get(DOMAIN)
+
+
+async def test_oauth_implementation_not_available(hass: HomeAssistant) -> None:
+    """Test that unavailable OAuth implementation raises ConfigEntryNotReady."""
+    config_entry = MockConfigEntry(
+        domain=DOMAIN,
+        unique_id="smappeeCloud",
+        source=SOURCE_USER,
+        data={
+            "auth_implementation": DOMAIN,
+            "token": {
+                "access_token": "mock-access-token",
+                "refresh_token": "mock-refresh-token",
+                "expires_at": 9999999999,
+                "token_type": "Bearer",
+            },
+        },
+    )
+    config_entry.add_to_hass(hass)
+
+    with patch(
+        "homeassistant.helpers.config_entry_oauth2_flow.async_get_config_entry_implementation",
+        side_effect=ImplementationUnavailableError,
+    ):
+        await hass.config_entries.async_setup(config_entry.entry_id)
+        await hass.async_block_till_done()
+
+    assert config_entry.state is ConfigEntryState.SETUP_RETRY