diff --git a/homeassistant/components/harmony/config_flow.py b/homeassistant/components/harmony/config_flow.py
index 16101f18cff..675acf600cb 100644
--- a/homeassistant/components/harmony/config_flow.py
+++ b/homeassistant/components/harmony/config_flow.py
@@ -3,6 +3,7 @@ from __future__ import annotations
 
 import asyncio
 import logging
+from typing import Any
 from urllib.parse import urlparse
 
 from aioharmony.hubconnector_websocket import HubConnector
@@ -57,7 +58,7 @@ class ConfigFlow(config_entries.ConfigFlow, domain=DOMAIN):
 
     def __init__(self) -> None:
         """Initialize the Harmony config flow."""
-        self.harmony_config = {}
+        self.harmony_config: dict[str, Any] = {}
 
     async def async_step_user(self, user_input=None):
         """Handle the initial step."""
diff --git a/homeassistant/components/harmony/data.py b/homeassistant/components/harmony/data.py
index aa373d5813a..fbbbbd38e3a 100644
--- a/homeassistant/components/harmony/data.py
+++ b/homeassistant/components/harmony/data.py
@@ -21,13 +21,14 @@ _LOGGER = logging.getLogger(__name__)
 class HarmonyData(HarmonySubscriberMixin):
     """HarmonyData registers for Harmony hub updates."""
 
-    def __init__(self, hass, address: str, name: str, unique_id: str):
+    _client: HarmonyClient
+
+    def __init__(self, hass, address: str, name: str, unique_id: str | None) -> None:
         """Initialize a data object."""
         super().__init__(hass)
         self._name = name
         self._unique_id = unique_id
         self._available = False
-        self._client = None
         self._address = address
 
     @property
@@ -99,7 +100,7 @@ class HarmonyData(HarmonySubscriberMixin):
             configuration_url="https://www.logitech.com/en-us/my-account",
         )
 
-    async def connect(self) -> bool:
+    async def connect(self) -> None:
         """Connect to the Harmony Hub."""
         _LOGGER.debug("%s: Connecting", self._name)
 
diff --git a/mypy.ini b/mypy.ini
index 77830664696..e7897368189 100644
--- a/mypy.ini
+++ b/mypy.ini
@@ -2674,15 +2674,6 @@ ignore_errors = true
 [mypy-homeassistant.components.google_assistant.trait]
 ignore_errors = true
 
-[mypy-homeassistant.components.harmony]
-ignore_errors = true
-
-[mypy-homeassistant.components.harmony.config_flow]
-ignore_errors = true
-
-[mypy-homeassistant.components.harmony.data]
-ignore_errors = true
-
 [mypy-homeassistant.components.hassio]
 ignore_errors = true
 
diff --git a/script/hassfest/mypy_config.py b/script/hassfest/mypy_config.py
index e9e78c2892b..f7b8bb1be2f 100644
--- a/script/hassfest/mypy_config.py
+++ b/script/hassfest/mypy_config.py
@@ -33,9 +33,6 @@ IGNORED_MODULES: Final[list[str]] = [
     "homeassistant.components.google_assistant.http",
     "homeassistant.components.google_assistant.report_state",
     "homeassistant.components.google_assistant.trait",
-    "homeassistant.components.harmony",
-    "homeassistant.components.harmony.config_flow",
-    "homeassistant.components.harmony.data",
     "homeassistant.components.hassio",
     "homeassistant.components.hassio.auth",
     "homeassistant.components.hassio.binary_sensor",