diff --git a/.coveragerc b/.coveragerc
index c887fc385e6..b267f6967ef 100644
--- a/.coveragerc
+++ b/.coveragerc
@@ -1014,7 +1014,6 @@ omit =
     homeassistant/components/watson_tts/tts.py
     homeassistant/components/waze_travel_time/sensor.py
     homeassistant/components/webostv/*
-    homeassistant/components/wemo/*
     homeassistant/components/whois/sensor.py
     homeassistant/components/wiffi/*
     homeassistant/components/wink/*
diff --git a/requirements_test_all.txt b/requirements_test_all.txt
index 9604d0579af..75f8f1cdece 100644
--- a/requirements_test_all.txt
+++ b/requirements_test_all.txt
@@ -932,6 +932,9 @@ pyvolumio==0.1.3
 # homeassistant.components.html5
 pywebpush==1.9.2
 
+# homeassistant.components.wemo
+pywemo==0.5.3
+
 # homeassistant.components.wilight
 pywilight==0.0.65
 
diff --git a/tests/components/wemo/__init__.py b/tests/components/wemo/__init__.py
new file mode 100644
index 00000000000..33bdcacd37d
--- /dev/null
+++ b/tests/components/wemo/__init__.py
@@ -0,0 +1 @@
+"""Tests for the wemo component."""
diff --git a/tests/components/wemo/conftest.py b/tests/components/wemo/conftest.py
new file mode 100644
index 00000000000..78262ccc59c
--- /dev/null
+++ b/tests/components/wemo/conftest.py
@@ -0,0 +1,75 @@
+"""Fixtures for pywemo."""
+import pytest
+import pywemo
+
+from homeassistant.components.wemo import CONF_DISCOVERY, CONF_STATIC
+from homeassistant.components.wemo.const import DOMAIN
+from homeassistant.setup import async_setup_component
+
+from tests.async_mock import create_autospec, patch
+
+MOCK_HOST = "127.0.0.1"
+MOCK_PORT = 50000
+MOCK_NAME = "WemoDeviceName"
+MOCK_SERIAL_NUMBER = "WemoSerialNumber"
+
+
+@pytest.fixture(name="pywemo_model")
+def pywemo_model_fixture():
+    """Fixture containing a pywemo class name used by pywemo_device_fixture."""
+    return "Insight"
+
+
+@pytest.fixture(name="pywemo_registry")
+def pywemo_registry_fixture():
+    """Fixture for SubscriptionRegistry instances."""
+    registry = create_autospec(pywemo.SubscriptionRegistry)
+
+    registry.callbacks = {}
+
+    def on_func(device, type_filter, callback):
+        registry.callbacks[device.name] = callback
+
+    registry.on.side_effect = on_func
+
+    with patch("pywemo.SubscriptionRegistry", return_value=registry):
+        yield registry
+
+
+@pytest.fixture(name="pywemo_device")
+def pywemo_device_fixture(pywemo_registry, pywemo_model):
+    """Fixture for WeMoDevice instances."""
+    device = create_autospec(getattr(pywemo, pywemo_model))
+    device.host = MOCK_HOST
+    device.port = MOCK_PORT
+    device.name = MOCK_NAME
+    device.serialnumber = MOCK_SERIAL_NUMBER
+    device.model_name = pywemo_model
+
+    url = f"http://{MOCK_HOST}:{MOCK_PORT}/setup.xml"
+    with patch("pywemo.setup_url_for_address", return_value=url), patch(
+        "pywemo.discovery.device_from_description", return_value=device
+    ):
+        yield device
+
+
+@pytest.fixture(name="wemo_entity")
+async def async_wemo_entity_fixture(hass, pywemo_device):
+    """Fixture for a Wemo entity in hass."""
+    assert await async_setup_component(
+        hass,
+        DOMAIN,
+        {
+            DOMAIN: {
+                CONF_DISCOVERY: False,
+                CONF_STATIC: [f"{MOCK_HOST}:{MOCK_PORT}"],
+            },
+        },
+    )
+    await hass.async_block_till_done()
+
+    entity_registry = await hass.helpers.entity_registry.async_get_registry()
+    entity_entries = list(entity_registry.entities.values())
+    assert len(entity_entries) == 1
+
+    yield entity_entries[0]
diff --git a/tests/components/wemo/test_binary_sensor.py b/tests/components/wemo/test_binary_sensor.py
new file mode 100644
index 00000000000..f217d0b168c
--- /dev/null
+++ b/tests/components/wemo/test_binary_sensor.py
@@ -0,0 +1,60 @@
+"""Tests for the Wemo binary_sensor entity."""
+
+import pytest
+
+from homeassistant.components.homeassistant import (
+    DOMAIN as HA_DOMAIN,
+    SERVICE_UPDATE_ENTITY,
+)
+from homeassistant.const import ATTR_ENTITY_ID, STATE_OFF, STATE_ON
+from homeassistant.setup import async_setup_component
+
+
+@pytest.fixture
+def pywemo_model():
+    """Pywemo Motion models use the binary_sensor platform."""
+    return "Motion"
+
+
+async def test_binary_sensor_registry_state_callback(
+    hass, pywemo_registry, pywemo_device, wemo_entity
+):
+    """Verify that the binary_sensor receives state updates from the registry."""
+    # On state.
+    pywemo_device.get_state.return_value = 1
+    pywemo_registry.callbacks[pywemo_device.name](pywemo_device, "", "")
+    await hass.async_block_till_done()
+    assert hass.states.get(wemo_entity.entity_id).state == STATE_ON
+
+    # Off state.
+    pywemo_device.get_state.return_value = 0
+    pywemo_registry.callbacks[pywemo_device.name](pywemo_device, "", "")
+    await hass.async_block_till_done()
+    assert hass.states.get(wemo_entity.entity_id).state == STATE_OFF
+
+
+async def test_binary_sensor_update_entity(
+    hass, pywemo_registry, pywemo_device, wemo_entity
+):
+    """Verify that the binary_sensor performs state updates."""
+    await async_setup_component(hass, HA_DOMAIN, {})
+
+    # On state.
+    pywemo_device.get_state.return_value = 1
+    await hass.services.async_call(
+        HA_DOMAIN,
+        SERVICE_UPDATE_ENTITY,
+        {ATTR_ENTITY_ID: [wemo_entity.entity_id]},
+        blocking=True,
+    )
+    assert hass.states.get(wemo_entity.entity_id).state == STATE_ON
+
+    # Off state.
+    pywemo_device.get_state.return_value = 0
+    await hass.services.async_call(
+        HA_DOMAIN,
+        SERVICE_UPDATE_ENTITY,
+        {ATTR_ENTITY_ID: [wemo_entity.entity_id]},
+        blocking=True,
+    )
+    assert hass.states.get(wemo_entity.entity_id).state == STATE_OFF
diff --git a/tests/components/wemo/test_fan.py b/tests/components/wemo/test_fan.py
new file mode 100644
index 00000000000..ed49519c771
--- /dev/null
+++ b/tests/components/wemo/test_fan.py
@@ -0,0 +1,85 @@
+"""Tests for the Wemo fan entity."""
+
+import pytest
+
+from homeassistant.components.homeassistant import (
+    DOMAIN as HA_DOMAIN,
+    SERVICE_UPDATE_ENTITY,
+)
+from homeassistant.components.wemo import fan
+from homeassistant.components.wemo.const import DOMAIN
+from homeassistant.const import ATTR_ENTITY_ID, STATE_OFF, STATE_ON
+from homeassistant.setup import async_setup_component
+
+
+@pytest.fixture
+def pywemo_model():
+    """Pywemo Humidifier models use the fan platform."""
+    return "Humidifier"
+
+
+async def test_fan_registry_state_callback(
+    hass, pywemo_registry, pywemo_device, wemo_entity
+):
+    """Verify that the fan receives state updates from the registry."""
+    # On state.
+    pywemo_device.get_state.return_value = 1
+    pywemo_registry.callbacks[pywemo_device.name](pywemo_device, "", "")
+    await hass.async_block_till_done()
+    assert hass.states.get(wemo_entity.entity_id).state == STATE_ON
+
+    # Off state.
+    pywemo_device.get_state.return_value = 0
+    pywemo_registry.callbacks[pywemo_device.name](pywemo_device, "", "")
+    await hass.async_block_till_done()
+    assert hass.states.get(wemo_entity.entity_id).state == STATE_OFF
+
+
+async def test_fan_update_entity(hass, pywemo_registry, pywemo_device, wemo_entity):
+    """Verify that the fan performs state updates."""
+    await async_setup_component(hass, HA_DOMAIN, {})
+
+    # On state.
+    pywemo_device.get_state.return_value = 1
+    await hass.services.async_call(
+        HA_DOMAIN,
+        SERVICE_UPDATE_ENTITY,
+        {ATTR_ENTITY_ID: [wemo_entity.entity_id]},
+        blocking=True,
+    )
+    assert hass.states.get(wemo_entity.entity_id).state == STATE_ON
+
+    # Off state.
+    pywemo_device.get_state.return_value = 0
+    await hass.services.async_call(
+        HA_DOMAIN,
+        SERVICE_UPDATE_ENTITY,
+        {ATTR_ENTITY_ID: [wemo_entity.entity_id]},
+        blocking=True,
+    )
+    assert hass.states.get(wemo_entity.entity_id).state == STATE_OFF
+
+
+async def test_fan_reset_filter_service(hass, pywemo_device, wemo_entity):
+    """Verify that SERVICE_RESET_FILTER_LIFE is registered and works."""
+    assert await hass.services.async_call(
+        DOMAIN,
+        fan.SERVICE_RESET_FILTER_LIFE,
+        {fan.ATTR_ENTITY_ID: wemo_entity.entity_id},
+        blocking=True,
+    )
+    pywemo_device.reset_filter_life.assert_called_with()
+
+
+async def test_fan_set_humidity_service(hass, pywemo_device, wemo_entity):
+    """Verify that SERVICE_SET_HUMIDITY is registered and works."""
+    assert await hass.services.async_call(
+        DOMAIN,
+        fan.SERVICE_SET_HUMIDITY,
+        {
+            fan.ATTR_ENTITY_ID: wemo_entity.entity_id,
+            fan.ATTR_TARGET_HUMIDITY: "50",
+        },
+        blocking=True,
+    )
+    pywemo_device.set_humidity.assert_called_with(fan.WEMO_HUMIDITY_50)
diff --git a/tests/components/wemo/test_light_bridge.py b/tests/components/wemo/test_light_bridge.py
new file mode 100644
index 00000000000..d76c714ba5e
--- /dev/null
+++ b/tests/components/wemo/test_light_bridge.py
@@ -0,0 +1,56 @@
+"""Tests for the Wemo light entity via the bridge."""
+
+import pytest
+import pywemo
+
+from homeassistant.components.homeassistant import (
+    DOMAIN as HA_DOMAIN,
+    SERVICE_UPDATE_ENTITY,
+)
+from homeassistant.const import ATTR_ENTITY_ID, STATE_OFF, STATE_ON
+from homeassistant.setup import async_setup_component
+
+from tests.async_mock import PropertyMock, create_autospec
+
+
+@pytest.fixture
+def pywemo_model():
+    """Pywemo Bridge models use the light platform (WemoLight class)."""
+    return "Bridge"
+
+
+@pytest.fixture(name="pywemo_bridge_light")
+def pywemo_bridge_light_fixture(pywemo_device):
+    """Fixture for Bridge.Light WeMoDevice instances."""
+    light = create_autospec(pywemo.ouimeaux_device.bridge.Light)
+    light.uniqueID = pywemo_device.serialnumber
+    light.name = pywemo_device.name
+    pywemo_device.Lights = {pywemo_device.serialnumber: light}
+    return light
+
+
+async def test_light_update_entity(
+    hass, pywemo_registry, pywemo_bridge_light, wemo_entity
+):
+    """Verify that the light performs state updates."""
+    await async_setup_component(hass, HA_DOMAIN, {})
+
+    # On state.
+    type(pywemo_bridge_light).state = PropertyMock(return_value={"onoff": 1})
+    await hass.services.async_call(
+        HA_DOMAIN,
+        SERVICE_UPDATE_ENTITY,
+        {ATTR_ENTITY_ID: [wemo_entity.entity_id]},
+        blocking=True,
+    )
+    assert hass.states.get(wemo_entity.entity_id).state == STATE_ON
+
+    # Off state.
+    type(pywemo_bridge_light).state = PropertyMock(return_value={"onoff": 0})
+    await hass.services.async_call(
+        HA_DOMAIN,
+        SERVICE_UPDATE_ENTITY,
+        {ATTR_ENTITY_ID: [wemo_entity.entity_id]},
+        blocking=True,
+    )
+    assert hass.states.get(wemo_entity.entity_id).state == STATE_OFF
diff --git a/tests/components/wemo/test_light_dimmer.py b/tests/components/wemo/test_light_dimmer.py
new file mode 100644
index 00000000000..e94634c6d15
--- /dev/null
+++ b/tests/components/wemo/test_light_dimmer.py
@@ -0,0 +1,58 @@
+"""Tests for the Wemo standalone/non-bridge light entity."""
+
+import pytest
+
+from homeassistant.components.homeassistant import (
+    DOMAIN as HA_DOMAIN,
+    SERVICE_UPDATE_ENTITY,
+)
+from homeassistant.const import ATTR_ENTITY_ID, STATE_OFF, STATE_ON
+from homeassistant.setup import async_setup_component
+
+
+@pytest.fixture
+def pywemo_model():
+    """Pywemo Dimmer models use the light platform (WemoDimmer class)."""
+    return "Dimmer"
+
+
+async def test_light_registry_state_callback(
+    hass, pywemo_registry, pywemo_device, wemo_entity
+):
+    """Verify that the light receives state updates from the registry."""
+    # On state.
+    pywemo_device.get_state.return_value = 1
+    pywemo_registry.callbacks[pywemo_device.name](pywemo_device, "", "")
+    await hass.async_block_till_done()
+    assert hass.states.get(wemo_entity.entity_id).state == STATE_ON
+
+    # Off state.
+    pywemo_device.get_state.return_value = 0
+    pywemo_registry.callbacks[pywemo_device.name](pywemo_device, "", "")
+    await hass.async_block_till_done()
+    assert hass.states.get(wemo_entity.entity_id).state == STATE_OFF
+
+
+async def test_light_update_entity(hass, pywemo_registry, pywemo_device, wemo_entity):
+    """Verify that the light performs state updates."""
+    await async_setup_component(hass, HA_DOMAIN, {})
+
+    # On state.
+    pywemo_device.get_state.return_value = 1
+    await hass.services.async_call(
+        HA_DOMAIN,
+        SERVICE_UPDATE_ENTITY,
+        {ATTR_ENTITY_ID: [wemo_entity.entity_id]},
+        blocking=True,
+    )
+    assert hass.states.get(wemo_entity.entity_id).state == STATE_ON
+
+    # Off state.
+    pywemo_device.get_state.return_value = 0
+    await hass.services.async_call(
+        HA_DOMAIN,
+        SERVICE_UPDATE_ENTITY,
+        {ATTR_ENTITY_ID: [wemo_entity.entity_id]},
+        blocking=True,
+    )
+    assert hass.states.get(wemo_entity.entity_id).state == STATE_OFF
diff --git a/tests/components/wemo/test_switch.py b/tests/components/wemo/test_switch.py
new file mode 100644
index 00000000000..1ae8e3f9455
--- /dev/null
+++ b/tests/components/wemo/test_switch.py
@@ -0,0 +1,58 @@
+"""Tests for the Wemo switch entity."""
+
+import pytest
+
+from homeassistant.components.homeassistant import (
+    DOMAIN as HA_DOMAIN,
+    SERVICE_UPDATE_ENTITY,
+)
+from homeassistant.const import ATTR_ENTITY_ID, STATE_OFF, STATE_ON
+from homeassistant.setup import async_setup_component
+
+
+@pytest.fixture
+def pywemo_model():
+    """Pywemo LightSwitch models use the switch platform."""
+    return "LightSwitch"
+
+
+async def test_switch_registry_state_callback(
+    hass, pywemo_registry, pywemo_device, wemo_entity
+):
+    """Verify that the switch receives state updates from the registry."""
+    # On state.
+    pywemo_device.get_state.return_value = 1
+    pywemo_registry.callbacks[pywemo_device.name](pywemo_device, "", "")
+    await hass.async_block_till_done()
+    assert hass.states.get(wemo_entity.entity_id).state == STATE_ON
+
+    # Off state.
+    pywemo_device.get_state.return_value = 0
+    pywemo_registry.callbacks[pywemo_device.name](pywemo_device, "", "")
+    await hass.async_block_till_done()
+    assert hass.states.get(wemo_entity.entity_id).state == STATE_OFF
+
+
+async def test_switch_update_entity(hass, pywemo_registry, pywemo_device, wemo_entity):
+    """Verify that the switch performs state updates."""
+    await async_setup_component(hass, HA_DOMAIN, {})
+
+    # On state.
+    pywemo_device.get_state.return_value = 1
+    await hass.services.async_call(
+        HA_DOMAIN,
+        SERVICE_UPDATE_ENTITY,
+        {ATTR_ENTITY_ID: [wemo_entity.entity_id]},
+        blocking=True,
+    )
+    assert hass.states.get(wemo_entity.entity_id).state == STATE_ON
+
+    # Off state.
+    pywemo_device.get_state.return_value = 0
+    await hass.services.async_call(
+        HA_DOMAIN,
+        SERVICE_UPDATE_ENTITY,
+        {ATTR_ENTITY_ID: [wemo_entity.entity_id]},
+        blocking=True,
+    )
+    assert hass.states.get(wemo_entity.entity_id).state == STATE_OFF