diff --git a/homeassistant/loader.py b/homeassistant/loader.py
index 622c8524709..71f746e322b 100644
--- a/homeassistant/loader.py
+++ b/homeassistant/loader.py
@@ -109,6 +109,12 @@ CUSTOM_WARNING = (
     "cause stability problems, be sure to disable it if you "
     "experience issues with Home Assistant"
 )
+IMPORT_EVENT_LOOP_WARNING = (
+    "We found an integration %s which is configured to "
+    "to import its code in the event loop. This component might "
+    "cause stability problems, be sure to disable it if you "
+    "experience issues with Home Assistant"
+)
 
 _UNDEF = object()  # Internal; not helpers.typing.UNDEFINED due to circular dependency
 
@@ -653,6 +659,9 @@ class Integration:
                 None if is_virtual else set(os.listdir(file_path)),
             )
 
+            if not integration.import_executor:
+                _LOGGER.warning(IMPORT_EVENT_LOOP_WARNING, integration.domain)
+
             if integration.is_built_in:
                 return integration
 
@@ -821,9 +830,8 @@ class Integration:
     def import_executor(self) -> bool:
         """Import integration in the executor."""
         # If the integration does not explicitly set import_executor, we default to
-        # True if it's a built-in integration and False if it's a custom integration.
-        # In the future, we want to default to True for all integrations.
-        return self.manifest.get("import_executor", self.is_built_in)
+        # True.
+        return self.manifest.get("import_executor", True)
 
     @cached_property
     def has_translations(self) -> bool:
diff --git a/tests/test_loader.py b/tests/test_loader.py
index 7828d197fc1..b51a9a846b8 100644
--- a/tests/test_loader.py
+++ b/tests/test_loader.py
@@ -1098,7 +1098,7 @@ async def test_async_suggest_report_issue(
 def test_import_executor_default(hass: HomeAssistant) -> None:
     """Test that import_executor defaults."""
     custom_comp = mock_integration(hass, MockModule("any_random"), built_in=False)
-    assert custom_comp.import_executor is False
+    assert custom_comp.import_executor is True
     built_in_comp = mock_integration(hass, MockModule("other_random"), built_in=True)
     assert built_in_comp.import_executor is True
 
@@ -1675,3 +1675,13 @@ async def test_async_get_platforms_concurrent_loads(
 
     assert imports == [button_module_name]
     assert integration.get_platform_cached("button") is button_module_mock
+
+
+async def test_integration_warnings(
+    hass: HomeAssistant,
+    enable_custom_integrations: None,
+    caplog: pytest.LogCaptureFixture,
+) -> None:
+    """Test integration warnings."""
+    await loader.async_get_integration(hass, "test_package_loaded_loop")
+    assert "configured to to import its code in the event loop" in caplog.text
diff --git a/tests/testing_config/custom_components/test_package_loaded_loop/__init__.py b/tests/testing_config/custom_components/test_package_loaded_loop/__init__.py
new file mode 100644
index 00000000000..c4d88fd17d7
--- /dev/null
+++ b/tests/testing_config/custom_components/test_package_loaded_loop/__init__.py
@@ -0,0 +1,7 @@
+"""Provide a mock package component."""
+from .const import TEST  # noqa: F401
+
+
+async def async_setup(hass, config):
+    """Mock a successful setup."""
+    return True
diff --git a/tests/testing_config/custom_components/test_package_loaded_loop/config_flow.py b/tests/testing_config/custom_components/test_package_loaded_loop/config_flow.py
new file mode 100644
index 00000000000..9153b666828
--- /dev/null
+++ b/tests/testing_config/custom_components/test_package_loaded_loop/config_flow.py
@@ -0,0 +1,7 @@
+"""Config flow."""
+
+from homeassistant.core import HomeAssistant
+
+
+async def _async_has_devices(hass: HomeAssistant) -> bool:
+    return True
diff --git a/tests/testing_config/custom_components/test_package_loaded_loop/const.py b/tests/testing_config/custom_components/test_package_loaded_loop/const.py
new file mode 100644
index 00000000000..7e13e04cb47
--- /dev/null
+++ b/tests/testing_config/custom_components/test_package_loaded_loop/const.py
@@ -0,0 +1,2 @@
+"""Constants for test_package custom component."""
+TEST = 5
diff --git a/tests/testing_config/custom_components/test_package_loaded_loop/manifest.json b/tests/testing_config/custom_components/test_package_loaded_loop/manifest.json
new file mode 100644
index 00000000000..e614d10b004
--- /dev/null
+++ b/tests/testing_config/custom_components/test_package_loaded_loop/manifest.json
@@ -0,0 +1,11 @@
+{
+  "domain": "test_package_loaded_loop",
+  "name": "Test Package that loads in the loop",
+  "documentation": "http://test-package.io",
+  "requirements": [],
+  "dependencies": [],
+  "codeowners": [],
+  "config_flow": true,
+  "import_executor": false,
+  "version": "1.2.3"
+}