diff --git a/homeassistant/components/sonos/switch.py b/homeassistant/components/sonos/switch.py
index acf33ea34aa..bbeda6edb63 100644
--- a/homeassistant/components/sonos/switch.py
+++ b/homeassistant/components/sonos/switch.py
@@ -16,6 +16,7 @@ from homeassistant.helpers import device_registry as dr, entity_registry as er
 from homeassistant.helpers.dispatcher import async_dispatcher_connect
 from homeassistant.helpers.entity import EntityCategory
 from homeassistant.helpers.entity_platform import AddEntitiesCallback
+from homeassistant.helpers.event import async_track_time_change
 
 from .const import (
     DATA_SONOS,
@@ -91,6 +92,8 @@ FEATURE_ICONS = {
     ATTR_TOUCH_CONTROLS: "mdi:gesture-tap",
 }
 
+WEEKEND_DAYS = (0, 6)
+
 
 async def async_setup_entry(
     hass: HomeAssistant,
@@ -233,6 +236,17 @@ class SonosAlarmEntity(SonosEntity, SwitchEntity):
             )
         )
 
+        async def async_write_state_daily(now: datetime.datetime) -> None:
+            """Update alarm state attributes each calendar day."""
+            _LOGGER.debug("Updating state attributes for %s", self.name)
+            self.async_write_ha_state()
+
+        self.async_on_remove(
+            async_track_time_change(
+                self.hass, async_write_state_daily, hour=0, minute=0, second=0
+            )
+        )
+
     @property
     def alarm(self) -> Alarm:
         """Return the alarm instance."""
@@ -304,14 +318,12 @@ class SonosAlarmEntity(SonosEntity, SwitchEntity):
     def _is_today(self) -> bool:
         """Return whether this alarm is scheduled for today."""
         recurrence = self.alarm.recurrence
-        timestr = int(datetime.datetime.today().strftime("%w"))
+        daynum = int(datetime.datetime.today().strftime("%w"))
         return (
-            bool(recurrence[:2] == "ON" and str(timestr) in recurrence)
-            or bool(recurrence == "DAILY")
-            or bool(recurrence == "WEEKDAYS" and int(timestr) not in [0, 7])
-            or bool(recurrence == "ONCE")
-            or bool(recurrence == "WEEKDAYS" and int(timestr) not in [0, 7])
-            or bool(recurrence == "WEEKENDS" and int(timestr) not in range(1, 7))
+            recurrence in ("DAILY", "ONCE")
+            or (recurrence == "WEEKENDS" and daynum in WEEKEND_DAYS)
+            or (recurrence == "WEEKDAYS" and daynum not in WEEKEND_DAYS)
+            or (recurrence.startswith("ON_") and str(daynum) in recurrence)
         )
 
     @property