diff --git a/homeassistant/components/notify/html5.py b/homeassistant/components/notify/html5.py
index f70a9cb73c1..6a486bb6362 100644
--- a/homeassistant/components/notify/html5.py
+++ b/homeassistant/components/notify/html5.py
@@ -7,6 +7,7 @@ https://home-assistant.io/components/notify.html5/
 import datetime
 import json
 import logging
+from functools import partial
 import time
 import uuid
 
@@ -20,7 +21,7 @@ from homeassistant.components.frontend import add_manifest_json_key
 from homeassistant.components.http import HomeAssistantView
 from homeassistant.components.notify import (
     ATTR_DATA, ATTR_TITLE, ATTR_TARGET, PLATFORM_SCHEMA, ATTR_TITLE_DEFAULT,
-    BaseNotificationService)
+    BaseNotificationService, DOMAIN)
 from homeassistant.const import (
     URL_ROOT, HTTP_BAD_REQUEST, HTTP_UNAUTHORIZED, HTTP_INTERNAL_SERVER_ERROR)
 from homeassistant.helpers import config_validation as cv
@@ -34,6 +35,8 @@ _LOGGER = logging.getLogger(__name__)
 
 REGISTRATIONS_FILE = 'html5_push_registrations.conf'
 
+SERVICE_DISMISS = 'html5_dismiss'
+
 ATTR_GCM_SENDER_ID = 'gcm_sender_id'
 ATTR_GCM_API_KEY = 'gcm_api_key'
 
@@ -57,6 +60,7 @@ ATTR_ACTION = 'action'
 ATTR_ACTIONS = 'actions'
 ATTR_TYPE = 'type'
 ATTR_URL = 'url'
+ATTR_DISMISS = 'dismiss'
 
 ATTR_JWT = 'jwt'
 
@@ -80,6 +84,11 @@ SUBSCRIPTION_SCHEMA = vol.All(
     })
 )
 
+DISMISS_SERVICE_SCHEMA = vol.Schema({
+    vol.Optional(ATTR_TARGET): vol.All(cv.ensure_list, [cv.string]),
+    vol.Optional(ATTR_DATA): dict,
+})
+
 REGISTER_SCHEMA = vol.Schema({
     vol.Required(ATTR_SUBSCRIPTION): SUBSCRIPTION_SCHEMA,
     vol.Required(ATTR_BROWSER): vol.In(['chrome', 'firefox']),
@@ -122,7 +131,8 @@ def get_service(hass, config, discovery_info=None):
         add_manifest_json_key(
             ATTR_GCM_SENDER_ID, config.get(ATTR_GCM_SENDER_ID))
 
-    return HTML5NotificationService(gcm_api_key, registrations, json_path)
+    return HTML5NotificationService(
+        hass, gcm_api_key, registrations, json_path)
 
 
 def _load_config(filename):
@@ -326,12 +336,29 @@ class HTML5PushCallbackView(HomeAssistantView):
 class HTML5NotificationService(BaseNotificationService):
     """Implement the notification service for HTML5."""
 
-    def __init__(self, gcm_key, registrations, json_path):
+    def __init__(self, hass, gcm_key, registrations, json_path):
         """Initialize the service."""
         self._gcm_key = gcm_key
         self.registrations = registrations
         self.registrations_json_path = json_path
 
+        async def async_dismiss_message(service):
+            """Handle dismissing notification message service calls."""
+            kwargs = {}
+
+            if self.targets is not None:
+                kwargs[ATTR_TARGET] = self.targets
+            elif service.data.get(ATTR_TARGET) is not None:
+                kwargs[ATTR_TARGET] = service.data.get(ATTR_TARGET)
+
+            kwargs[ATTR_DATA] = service.data.get(ATTR_DATA)
+
+            await self.async_dismiss(**kwargs)
+
+        hass.services.async_register(
+            DOMAIN, SERVICE_DISMISS, async_dismiss_message,
+            schema=DISMISS_SERVICE_SCHEMA)
+
     @property
     def targets(self):
         """Return a dictionary of registered targets."""
@@ -340,12 +367,28 @@ class HTML5NotificationService(BaseNotificationService):
             targets[registration] = registration
         return targets
 
+    def dismiss(self, **kwargs):
+        """Dismisses a notification."""
+        data = kwargs.get(ATTR_DATA)
+        tag = data.get(ATTR_TAG) if data else ""
+        payload = {
+            ATTR_TAG: tag,
+            ATTR_DISMISS: True,
+            ATTR_DATA: {}
+        }
+
+        self._push_message(payload, **kwargs)
+
+    async def async_dismiss(self, **kwargs):
+        """Dismisses a notification.
+
+        This method must be run in the event loop.
+        """
+        await self.hass.async_add_executor_job(
+            partial(self.dismiss, **kwargs))
+
     def send_message(self, message="", **kwargs):
         """Send a message to a user."""
-        import jwt
-        from pywebpush import WebPusher
-
-        timestamp = int(time.time())
         tag = str(uuid.uuid4())
 
         payload = {
@@ -354,7 +397,6 @@ class HTML5NotificationService(BaseNotificationService):
             ATTR_DATA: {},
             'icon': '/static/icons/favicon-192x192.png',
             ATTR_TAG: tag,
-            'timestamp': (timestamp*1000),  # Javascript ms since epoch
             ATTR_TITLE: kwargs.get(ATTR_TITLE, ATTR_TITLE_DEFAULT)
         }
 
@@ -378,6 +420,17 @@ class HTML5NotificationService(BaseNotificationService):
                 payload.get(ATTR_ACTIONS) is None):
             payload[ATTR_DATA][ATTR_URL] = URL_ROOT
 
+        self._push_message(payload, **kwargs)
+
+    def _push_message(self, payload, **kwargs):
+        """Send the message."""
+        import jwt
+        from pywebpush import WebPusher
+
+        timestamp = int(time.time())
+
+        payload['timestamp'] = (timestamp*1000)  # Javascript ms since epoch
+
         targets = kwargs.get(ATTR_TARGET)
 
         if not targets:
diff --git a/homeassistant/components/notify/services.yaml b/homeassistant/components/notify/services.yaml
index 23b1c968c4a..1b7944cc7da 100644
--- a/homeassistant/components/notify/services.yaml
+++ b/homeassistant/components/notify/services.yaml
@@ -16,6 +16,16 @@ notify:
       description: Extended information for notification. Optional depending on the platform.
       example: platform specific
 
+html5_dismiss:
+  description: Dismiss a html5 notification.
+  fields:
+    target:
+      description: An array of targets. Optional.
+      example: ['my_phone', 'my_tablet']
+    data:
+      description: Extended information of notification. Supports tag. Optional.
+      example: '{ "tag": "tagname" }'
+
 apns_register:
   description: Registers a device to receive push notifications.
   fields:
diff --git a/tests/components/notify/test_html5.py b/tests/components/notify/test_html5.py
index 6aeba650a8c..e33c297b166 100644
--- a/tests/components/notify/test_html5.py
+++ b/tests/components/notify/test_html5.py
@@ -81,6 +81,40 @@ class TestHtml5Notify:
 
         assert service is not None
 
+    @patch('pywebpush.WebPusher')
+    def test_dismissing_message(self, mock_wp):
+        """Test dismissing message."""
+        hass = MagicMock()
+
+        data = {
+            'device': SUBSCRIPTION_1
+        }
+
+        m = mock_open(read_data=json.dumps(data))
+        with patch(
+            'homeassistant.util.json.open',
+            m, create=True
+        ):
+            service = html5.get_service(hass, {'gcm_sender_id': '100'})
+
+        assert service is not None
+
+        service.dismiss(target=['device', 'non_existing'],
+                        data={'tag': 'test'})
+
+        assert len(mock_wp.mock_calls) == 3
+
+        # WebPusher constructor
+        assert mock_wp.mock_calls[0][1][0] == SUBSCRIPTION_1['subscription']
+        # Third mock_call checks the status_code of the response.
+        assert mock_wp.mock_calls[2][0] == '().send().status_code.__eq__'
+
+        # Call to send
+        payload = json.loads(mock_wp.mock_calls[1][1][0])
+
+        assert payload['dismiss'] is True
+        assert payload['tag'] == 'test'
+
     @patch('pywebpush.WebPusher')
     def test_sending_message(self, mock_wp):
         """Test sending message."""