diff --git a/homeassistant/components/mqtt/switch.py b/homeassistant/components/mqtt/switch.py
index fb33c16fd74..c11e843fc9b 100644
--- a/homeassistant/components/mqtt/switch.py
+++ b/homeassistant/components/mqtt/switch.py
@@ -90,18 +90,17 @@ class MqttSwitch(MqttEntity, SwitchEntity, RestoreEntity):
     def _setup_from_config(self, config: ConfigType) -> None:
         """(Re)Setup the entity."""
         self._attr_device_class = config.get(CONF_DEVICE_CLASS)
-
         state_on: str | None = config.get(CONF_STATE_ON)
-        self._state_on = state_on if state_on else config[CONF_PAYLOAD_ON]
-
         state_off: str | None = config.get(CONF_STATE_OFF)
-        self._state_off = state_off if state_off else config[CONF_PAYLOAD_OFF]
-
+        self._is_on_map = {
+            state_on if state_on else config[CONF_PAYLOAD_ON]: True,
+            state_off if state_off else config[CONF_PAYLOAD_OFF]: False,
+            PAYLOAD_NONE: None,
+        }
         self._optimistic = (
             config[CONF_OPTIMISTIC] or config.get(CONF_STATE_TOPIC) is None
         )
         self._attr_assumed_state = bool(self._optimistic)
-
         self._value_template = MqttValueTemplate(
             self._config.get(CONF_VALUE_TEMPLATE), entity=self
         ).async_render_with_possible_json_value
@@ -109,13 +108,8 @@ class MqttSwitch(MqttEntity, SwitchEntity, RestoreEntity):
     @callback
     def _state_message_received(self, msg: ReceiveMessage) -> None:
         """Handle new MQTT state messages."""
-        payload = self._value_template(msg.payload)
-        if payload == self._state_on:
-            self._attr_is_on = True
-        elif payload == self._state_off:
-            self._attr_is_on = False
-        elif payload == PAYLOAD_NONE:
-            self._attr_is_on = None
+        if (payload := self._value_template(msg.payload)) in self._is_on_map:
+            self._attr_is_on = self._is_on_map[payload]
 
     @callback
     def _prepare_subscribe_topics(self) -> None: