diff --git a/homeassistant/components/simplisafe/alarm_control_panel.py b/homeassistant/components/simplisafe/alarm_control_panel.py
index 37aa2d84585..362c0244749 100644
--- a/homeassistant/components/simplisafe/alarm_control_panel.py
+++ b/homeassistant/components/simplisafe/alarm_control_panel.py
@@ -19,7 +19,9 @@ from homeassistant.const import (
     CONF_CODE,
     STATE_ALARM_ARMED_AWAY,
     STATE_ALARM_ARMED_HOME,
+    STATE_ALARM_ARMING,
     STATE_ALARM_DISARMED,
+    STATE_ALARM_TRIGGERED,
 )
 from homeassistant.util.dt import utc_from_timestamp
 
@@ -28,7 +30,6 @@ from .const import DATA_CLIENT, DOMAIN
 
 _LOGGER = logging.getLogger(__name__)
 
-ATTR_ALARM_ACTIVE = "alarm_active"
 ATTR_ALARM_DURATION = "alarm_duration"
 ATTR_ALARM_VOLUME = "alarm_volume"
 ATTR_BATTERY_BACKUP_POWER_LEVEL = "battery_backup_power_level"
@@ -80,7 +81,6 @@ class SimpliSafeAlarm(SimpliSafeEntity, AlarmControlPanel):
         self._simplisafe = simplisafe
         self._state = None
 
-        self._attrs.update({ATTR_ALARM_ACTIVE: self._system.alarm_going_off})
         if self._system.version == 3:
             self._attrs.update(
                 {
@@ -157,10 +157,10 @@ class SimpliSafeAlarm(SimpliSafeEntity, AlarmControlPanel):
 
     async def async_update(self):
         """Update alarm status."""
-        event_data = self._simplisafe.last_event_data[self._system.system_id]
+        last_event = self._simplisafe.last_event_data[self._system.system_id]
 
-        if event_data.get("pinName"):
-            self._changed_by = event_data["pinName"]
+        if last_event.get("pinName"):
+            self._changed_by = last_event["pinName"]
 
         if self._system.state == SystemStates.error:
             self._online = False
@@ -168,21 +168,23 @@ class SimpliSafeAlarm(SimpliSafeEntity, AlarmControlPanel):
 
         self._online = True
 
-        if self._system.state == SystemStates.off:
-            self._state = STATE_ALARM_DISARMED
-        elif self._system.state in (SystemStates.home, SystemStates.home_count):
-            self._state = STATE_ALARM_ARMED_HOME
+        if self._system.alarm_going_off:
+            self._state = STATE_ALARM_TRIGGERED
+        elif self._system.state == SystemStates.away:
+            self._state = STATE_ALARM_ARMED_AWAY
         elif self._system.state in (
-            SystemStates.away,
             SystemStates.away_count,
             SystemStates.exit_delay,
+            SystemStates.home_count,
         ):
-            self._state = STATE_ALARM_ARMED_AWAY
+            self._state = STATE_ALARM_ARMING
+        elif self._system.state == SystemStates.home:
+            self._state = STATE_ALARM_ARMED_HOME
+        elif self._system.state == SystemStates.off:
+            self._state = STATE_ALARM_DISARMED
         else:
             self._state = None
 
-        last_event = self._simplisafe.last_event_data[self._system.system_id]
-
         try:
             last_event_sensor_type = EntityTypes(last_event["sensorType"]).name
         except ValueError: