diff --git a/homeassistant/components/x10/light.py b/homeassistant/components/x10/light.py
index 0676b249e1b..f007b799bf6 100644
--- a/homeassistant/components/x10/light.py
+++ b/homeassistant/components/x10/light.py
@@ -8,8 +8,8 @@ import voluptuous as vol
 
 from homeassistant.components.light import (
     ATTR_BRIGHTNESS,
+    COLOR_MODE_BRIGHTNESS,
     PLATFORM_SCHEMA,
-    SUPPORT_BRIGHTNESS,
     LightEntity,
 )
 from homeassistant.const import CONF_DEVICES, CONF_ID, CONF_NAME
@@ -20,8 +20,6 @@ from homeassistant.helpers.typing import ConfigType, DiscoveryInfoType
 
 _LOGGER = logging.getLogger(__name__)
 
-SUPPORT_X10 = SUPPORT_BRIGHTNESS
-
 PLATFORM_SCHEMA = PLATFORM_SCHEMA.extend(
     {
         vol.Required(CONF_DEVICES): vol.All(
@@ -63,6 +61,9 @@ def setup_platform(
 class X10Light(LightEntity):
     """Representation of an X10 Light."""
 
+    _attr_color_mode = COLOR_MODE_BRIGHTNESS
+    _attr_supported_color_modes = {COLOR_MODE_BRIGHTNESS}
+
     def __init__(self, light, is_cm11a):
         """Initialize an X10 Light."""
         self._name = light["name"]
@@ -86,11 +87,6 @@ class X10Light(LightEntity):
         """Return true if light is on."""
         return self._state
 
-    @property
-    def supported_features(self):
-        """Flag supported features."""
-        return SUPPORT_X10
-
     def turn_on(self, **kwargs):
         """Instruct the light to turn on."""
         if self._is_cm11a: