diff --git a/tests/unit_tests/core/test_config.py b/tests/unit_tests/core/test_config.py
index 372c1df7ee..55cc1f3027 100644
--- a/tests/unit_tests/core/test_config.py
+++ b/tests/unit_tests/core/test_config.py
@@ -28,13 +28,6 @@ def yaml_file(tmp_path: Path) -> Callable[[str], str]:
     return _yaml_file
 
 
-@pytest.fixture(autouse=True)
-def reset_core():
-    """Reset CORE after each test."""
-    yield
-    CORE.reset()
-
-
 def load_config_from_yaml(
     yaml_file: Callable[[str], str], yaml_content: str
 ) -> Config | None:
@@ -61,7 +54,7 @@ def load_config_from_fixture(
 
 def test_validate_area_config_with_string() -> None:
     """Test that string area config is converted to structured format."""
-    result: dict[str, Any] = validate_area_config("Living Room")
+    result = validate_area_config("Living Room")
 
     assert isinstance(result, dict)
     assert "id" in result
@@ -80,7 +73,7 @@ def test_validate_area_config_with_dict() -> None:
         "name": "Test Area",
     }
 
-    result: dict[str, Any] = validate_area_config(input_config)
+    result = validate_area_config(input_config)
 
     assert result == input_config
     assert result["id"] == area_id
diff --git a/tests/unit_tests/test_entity.py b/tests/unit_tests/test_entity.py
index 3033b52a65..1b0c648be4 100644
--- a/tests/unit_tests/test_entity.py
+++ b/tests/unit_tests/test_entity.py
@@ -13,6 +13,9 @@ from esphome.cpp_generator import MockObj
 from esphome.entity import get_base_entity_object_id, setup_entity
 from esphome.helpers import sanitize, snake_case
 
+# Pre-compiled regex pattern for extracting object IDs from expressions
+OBJECT_ID_PATTERN = re.compile(r'\.set_object_id\(["\'](.*?)["\']\)')
+
 
 @pytest.fixture(autouse=True)
 def restore_core_state() -> Generator[None, None, None]:
@@ -256,7 +259,7 @@ def extract_object_id_from_expressions(expressions: list[str]) -> str | None:
     for expr in expressions:
         # Look for set_object_id calls with regex to handle various formats
         # Matches: var.set_object_id("temperature_2") or var.set_object_id('temperature_2')
-        match = re.search(r'\.set_object_id\(["\'](.*?)["\']\)', expr)
+        match = OBJECT_ID_PATTERN.search(expr)
         if match:
             return match.group(1)
     return None