diff --git a/homeassistant/components/fitbit/__init__.py b/homeassistant/components/fitbit/__init__.py
index f2378797d8d..6b4e1cadbf3 100644
--- a/homeassistant/components/fitbit/__init__.py
+++ b/homeassistant/components/fitbit/__init__.py
@@ -4,9 +4,12 @@ from homeassistant.const import Platform
 from homeassistant.core import HomeAssistant
 from homeassistant.exceptions import ConfigEntryAuthFailed, ConfigEntryNotReady
 from homeassistant.helpers import config_entry_oauth2_flow
+from homeassistant.helpers.config_entry_oauth2_flow import (
+    ImplementationUnavailableError,
+)
 
 from . import api
-from .const import FitbitScope
+from .const import DOMAIN, FitbitScope
 from .coordinator import FitbitConfigEntry, FitbitData, FitbitDeviceCoordinator
 from .exceptions import FitbitApiException, FitbitAuthException
 from .model import config_from_entry_data
@@ -16,11 +19,17 @@ PLATFORMS: list[Platform] = [Platform.SENSOR]
 
 async def async_setup_entry(hass: HomeAssistant, entry: FitbitConfigEntry) -> bool:
     """Set up fitbit from a config entry."""
-    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 ImplementationUnavailableError as err:
+        raise ConfigEntryNotReady(
+            translation_domain=DOMAIN,
+            translation_key="oauth2_implementation_unavailable",
+        ) from err
     session = config_entry_oauth2_flow.OAuth2Session(hass, entry, implementation)
     fitbit_api = api.OAuthFitbitApi(
         hass, session, unit_system=entry.data.get("unit_system")
diff --git a/homeassistant/components/fitbit/strings.json b/homeassistant/components/fitbit/strings.json
index 4d9060b9987..49281a78560 100644
--- a/homeassistant/components/fitbit/strings.json
+++ b/homeassistant/components/fitbit/strings.json
@@ -121,5 +121,10 @@
         "name": "Water"
       }
     }
+  },
+  "exceptions": {
+    "oauth2_implementation_unavailable": {
+      "message": "[%key:common::exceptions::oauth2_implementation_unavailable::message%]"
+    }
   }
 }
diff --git a/tests/components/fitbit/test_init.py b/tests/components/fitbit/test_init.py
index 277965848c4..be6b052a840 100644
--- a/tests/components/fitbit/test_init.py
+++ b/tests/components/fitbit/test_init.py
@@ -2,6 +2,7 @@
 
 from collections.abc import Awaitable, Callable
 from http import HTTPStatus
+from unittest.mock import patch
 
 import pytest
 
@@ -12,6 +13,9 @@ from homeassistant.components.fitbit.const import (
 )
 from homeassistant.config_entries import ConfigEntryState
 from homeassistant.core import HomeAssistant
+from homeassistant.helpers.config_entry_oauth2_flow import (
+    ImplementationUnavailableError,
+)
 
 from .conftest import (
     CLIENT_ID,
@@ -26,6 +30,23 @@ from tests.common import MockConfigEntry
 from tests.test_util.aiohttp import AiohttpClientMocker
 
 
+async def test_oauth_implementation_not_available(
+    hass: HomeAssistant,
+    config_entry: MockConfigEntry,
+) -> None:
+    """Test that unavailable OAuth implementation raises ConfigEntryNotReady."""
+    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
+
+
 async def test_setup(
     hass: HomeAssistant,
     integration_setup: Callable[[], Awaitable[bool]],