diff --git a/esphome/loader.py b/esphome/loader.py
index 7b2472521a..ec2f5101da 100644
--- a/esphome/loader.py
+++ b/esphome/loader.py
@@ -192,7 +192,7 @@ def install_custom_components_meta_finder():
     install_meta_finder(custom_components_dir)
 
 
-def _lookup_module(domain, exception):
+def _lookup_module(domain: str, exception: bool) -> ComponentManifest | None:
     if domain in _COMPONENT_CACHE:
         return _COMPONENT_CACHE[domain]
 
@@ -219,16 +219,16 @@ def _lookup_module(domain, exception):
     return manif
 
 
-def get_component(domain, exception=False):
+def get_component(domain: str, exception: bool = False) -> ComponentManifest | None:
     assert "." not in domain
     return _lookup_module(domain, exception)
 
 
-def get_platform(domain, platform):
+def get_platform(domain: str, platform: str) -> ComponentManifest | None:
     full = f"{platform}.{domain}"
     return _lookup_module(full, False)
 
 
-_COMPONENT_CACHE = {}
+_COMPONENT_CACHE: dict[str, ComponentManifest] = {}
 CORE_COMPONENTS_PATH = (Path(__file__).parent / "components").resolve()
 _COMPONENT_CACHE["esphome"] = ComponentManifest(esphome.core.config)