diff --git a/homeassistant/components/tag/__init__.py b/homeassistant/components/tag/__init__.py
index 01b283bb778..43dc8ce5db7 100644
--- a/homeassistant/components/tag/__init__.py
+++ b/homeassistant/components/tag/__init__.py
@@ -13,15 +13,13 @@ from homeassistant.helpers.storage import Store
 from homeassistant.loader import bind_hass
 import homeassistant.util.dt as dt_util
 
-from .const import DOMAIN
+from .const import DEVICE_ID, DOMAIN, EVENT_TAG_SCANNED, TAG_ID
 
 _LOGGER = logging.getLogger(__name__)
-DEVICE_ID = "device_id"
-EVENT_TAG_SCANNED = "tag_scanned"
+
 LAST_SCANNED = "last_scanned"
 STORAGE_KEY = DOMAIN
 STORAGE_VERSION = 1
-TAG_ID = "tag_id"
 TAGS = "tags"
 
 CREATE_FIELDS = {
diff --git a/homeassistant/components/tag/const.py b/homeassistant/components/tag/const.py
index 60f6e05c27e..ed74a1f0549 100644
--- a/homeassistant/components/tag/const.py
+++ b/homeassistant/components/tag/const.py
@@ -1,3 +1,6 @@
 """Constants for the Tag integration."""
 
+DEVICE_ID = "device_id"
 DOMAIN = "tag"
+EVENT_TAG_SCANNED = "tag_scanned"
+TAG_ID = "tag_id"
diff --git a/homeassistant/components/tag/trigger.py b/homeassistant/components/tag/trigger.py
new file mode 100644
index 00000000000..8da9baa5aaa
--- /dev/null
+++ b/homeassistant/components/tag/trigger.py
@@ -0,0 +1,37 @@
+"""Support for tag triggers."""
+import voluptuous as vol
+
+from homeassistant.components.homeassistant.triggers import event as event_trigger
+from homeassistant.const import CONF_PLATFORM
+from homeassistant.helpers import config_validation as cv
+
+from .const import DEVICE_ID, DOMAIN, EVENT_TAG_SCANNED, TAG_ID
+
+TRIGGER_SCHEMA = vol.Schema(
+    {
+        vol.Required(CONF_PLATFORM): DOMAIN,
+        vol.Required(TAG_ID): cv.string,
+        vol.Optional(DEVICE_ID): cv.string,
+    }
+)
+
+
+async def async_attach_trigger(hass, config, action, automation_info):
+    """Listen for tag_scanned events based on configuration."""
+    tag_id = config.get(TAG_ID)
+    device_id = config.get(DEVICE_ID)
+    event_data = {TAG_ID: tag_id}
+
+    if device_id:
+        event_data[DEVICE_ID] = device_id
+
+    event_config = {
+        event_trigger.CONF_PLATFORM: "event",
+        event_trigger.CONF_EVENT_TYPE: EVENT_TAG_SCANNED,
+        event_trigger.CONF_EVENT_DATA: event_data,
+    }
+    event_config = event_trigger.TRIGGER_SCHEMA(event_config)
+
+    return await event_trigger.async_attach_trigger(
+        hass, event_config, action, automation_info, platform_type=DOMAIN
+    )
diff --git a/tests/components/tag/test_trigger.py b/tests/components/tag/test_trigger.py
new file mode 100644
index 00000000000..0249acaf29b
--- /dev/null
+++ b/tests/components/tag/test_trigger.py
@@ -0,0 +1,85 @@
+"""Tests for tag triggers."""
+
+import pytest
+
+import homeassistant.components.automation as automation
+from homeassistant.components.tag import async_scan_tag
+from homeassistant.components.tag.const import DOMAIN, TAG_ID
+from homeassistant.setup import async_setup_component
+
+from tests.common import async_mock_service
+
+
+@pytest.fixture
+def tag_setup(hass, hass_storage):
+    """Tag setup."""
+
+    async def _storage(items=None):
+        if items is None:
+            hass_storage[DOMAIN] = {
+                "key": DOMAIN,
+                "version": 1,
+                "data": {"items": [{"id": "test tag"}]},
+            }
+        else:
+            hass_storage[DOMAIN] = items
+        config = {DOMAIN: {}}
+        return await async_setup_component(hass, DOMAIN, config)
+
+    return _storage
+
+
+@pytest.fixture
+def calls(hass):
+    """Track calls to a mock service."""
+    return async_mock_service(hass, "test", "automation")
+
+
+async def test_triggers(hass, tag_setup, calls):
+    """Test tag triggers."""
+    assert await tag_setup()
+    assert await async_setup_component(
+        hass,
+        automation.DOMAIN,
+        {
+            automation.DOMAIN: [
+                {
+                    "trigger": {"platform": DOMAIN, TAG_ID: "abc123"},
+                    "action": {
+                        "service": "test.automation",
+                        "data": {"message": "service called"},
+                    },
+                }
+            ]
+        },
+    )
+
+    await hass.async_block_till_done()
+
+    await async_scan_tag(hass, "abc123", None)
+    await hass.async_block_till_done()
+
+    assert len(calls) == 1
+    assert calls[0].data["message"] == "service called"
+
+
+async def test_exception_bad_trigger(hass, calls, caplog):
+    """Test for exception on event triggers firing."""
+
+    await async_setup_component(
+        hass,
+        automation.DOMAIN,
+        {
+            automation.DOMAIN: [
+                {
+                    "trigger": {"trigger": {"platform": DOMAIN, "oops": "abc123"}},
+                    "action": {
+                        "service": "test.automation",
+                        "data": {"message": "service called"},
+                    },
+                }
+            ]
+        },
+    )
+    await hass.async_block_till_done()
+    assert "Invalid config for [automation]" in caplog.text