diff --git a/homeassistant/components/notify/__init__.py b/homeassistant/components/notify/__init__.py
index 00047f0a32b..f3c2778bc59 100644
--- a/homeassistant/components/notify/__init__.py
+++ b/homeassistant/components/notify/__init__.py
@@ -10,9 +10,9 @@ import voluptuous as vol
 
 import homeassistant.components.persistent_notification as pn
 from homeassistant.const import CONF_DESCRIPTION, CONF_NAME, CONF_PLATFORM
-from homeassistant.core import HomeAssistant, ServiceCall
+from homeassistant.core import HomeAssistant, ServiceCall, callback
 from homeassistant.exceptions import HomeAssistantError
-from homeassistant.helpers import config_per_platform, discovery
+from homeassistant.helpers import config_per_platform, discovery, template
 import homeassistant.helpers.config_validation as cv
 from homeassistant.helpers.service import async_set_service_schema
 from homeassistant.loader import async_get_integration, bind_hass
@@ -68,6 +68,19 @@ PERSISTENT_NOTIFICATION_SERVICE_SCHEMA = vol.Schema(
 )
 
 
+@callback
+def _check_templates_warn(hass: HomeAssistant, tpl: template.Template) -> None:
+    """Warn user that passing templates to notify service is deprecated."""
+    if tpl.is_static or hass.data.get("notify_template_warned"):
+        return
+
+    hass.data["notify_template_warned"] = True
+    _LOGGER.warning(
+        "Passing templates to notify service is deprecated and will be removed in 2021.12. "
+        "Automations and scripts handle templates automatically"
+    )
+
+
 @bind_hass
 async def async_reload(hass: HomeAssistant, integration_name: str) -> None:
     """Register notify services for an integration."""
@@ -144,6 +157,7 @@ class BaseNotificationService:
         title = service.data.get(ATTR_TITLE)
 
         if title:
+            _check_templates_warn(self.hass, title)
             title.hass = self.hass
             kwargs[ATTR_TITLE] = title.async_render(parse_result=False)
 
@@ -152,6 +166,7 @@ class BaseNotificationService:
         elif service.data.get(ATTR_TARGET) is not None:
             kwargs[ATTR_TARGET] = service.data.get(ATTR_TARGET)
 
+        _check_templates_warn(self.hass, message)
         message.hass = self.hass
         kwargs[ATTR_MESSAGE] = message.async_render(parse_result=False)
         kwargs[ATTR_DATA] = service.data.get(ATTR_DATA)
@@ -261,10 +276,12 @@ async def async_setup(hass, config):
         payload = {}
         message = service.data[ATTR_MESSAGE]
         message.hass = hass
+        _check_templates_warn(hass, message)
         payload[ATTR_MESSAGE] = message.async_render(parse_result=False)
 
         title = service.data.get(ATTR_TITLE)
         if title:
+            _check_templates_warn(hass, title)
             title.hass = hass
             payload[ATTR_TITLE] = title.async_render(parse_result=False)
 
diff --git a/tests/components/notify/test_init.py b/tests/components/notify/test_init.py
index cce26750c1c..92b71091e07 100644
--- a/tests/components/notify/test_init.py
+++ b/tests/components/notify/test_init.py
@@ -1,6 +1,7 @@
 """The tests for notify services that change targets."""
 from homeassistant.components import notify
 from homeassistant.core import HomeAssistant
+from homeassistant.setup import async_setup_component
 
 
 async def test_same_targets(hass: HomeAssistant):
@@ -81,3 +82,19 @@ class NotificationService(notify.BaseNotificationService):
     def targets(self):
         """Return a dictionary of devices."""
         return self.target_list
+
+
+async def test_warn_template(hass, caplog):
+    """Test warning when template used."""
+    assert await async_setup_component(hass, "notify", {})
+    assert await async_setup_component(hass, "persistent_notification", {})
+
+    await hass.services.async_call(
+        "notify",
+        "persistent_notification",
+        {"message": "{{ 1 + 1 }}", "title": "Test notif {{ 1 + 1 }}"},
+        blocking=True,
+    )
+    # We should only log it once
+    assert caplog.text.count("Passing templates to notify service is deprecated") == 1
+    assert hass.states.get("persistent_notification.notification") is not None