diff --git a/homeassistant/components/mqtt/fan.py b/homeassistant/components/mqtt/fan.py
index f6d60ae8cbe..f5b347d6b71 100644
--- a/homeassistant/components/mqtt/fan.py
+++ b/homeassistant/components/mqtt/fan.py
@@ -94,6 +94,8 @@ DEFAULT_SPEED_RANGE_MAX = 100
 OSCILLATE_ON_PAYLOAD = "oscillate_on"
 OSCILLATE_OFF_PAYLOAD = "oscillate_off"
 
+PAYLOAD_NONE = "None"
+
 MQTT_FAN_ATTRIBUTES_BLOCKED = frozenset(
     {
         fan.ATTR_DIRECTION,
@@ -243,7 +245,7 @@ class MqttFan(MqttEntity, FanEntity):
 
     def __init__(self, hass, config, config_entry, discovery_data):
         """Initialize the MQTT fan."""
-        self._state = False
+        self._state = None
         self._percentage = None
         self._preset_mode = None
         self._oscillation = None
@@ -367,6 +369,8 @@ class MqttFan(MqttEntity, FanEntity):
                 self._state = True
             elif payload == self._payload["STATE_OFF"]:
                 self._state = False
+            elif payload == PAYLOAD_NONE:
+                self._state = None
             self.async_write_ha_state()
 
         if self._topic[CONF_STATE_TOPIC] is not None:
@@ -493,7 +497,7 @@ class MqttFan(MqttEntity, FanEntity):
         return self._optimistic
 
     @property
-    def is_on(self):
+    def is_on(self) -> bool | None:
         """Return true if device is on."""
         return self._state
 
diff --git a/tests/components/mqtt/test_fan.py b/tests/components/mqtt/test_fan.py
index 0a3b2499dc2..ecc1f15c204 100644
--- a/tests/components/mqtt/test_fan.py
+++ b/tests/components/mqtt/test_fan.py
@@ -27,6 +27,7 @@ from homeassistant.const import (
     ATTR_SUPPORTED_FEATURES,
     STATE_OFF,
     STATE_ON,
+    STATE_UNKNOWN,
 )
 from homeassistant.setup import async_setup_component
 
@@ -119,7 +120,7 @@ async def test_controlling_state_via_topic(hass, mqtt_mock, caplog):
     await hass.async_block_till_done()
 
     state = hass.states.get("fan.test")
-    assert state.state == STATE_OFF
+    assert state.state == STATE_UNKNOWN
     assert not state.attributes.get(ATTR_ASSUMED_STATE)
 
     async_fire_mqtt_message(hass, "state-topic", "StAtE_On")
@@ -194,6 +195,10 @@ async def test_controlling_state_via_topic(hass, mqtt_mock, caplog):
     assert state.attributes.get(fan.ATTR_PERCENTAGE) is None
     assert state.attributes.get(fan.ATTR_SPEED) is None
 
+    async_fire_mqtt_message(hass, "state-topic", "None")
+    state = hass.states.get("fan.test")
+    assert state.state == STATE_UNKNOWN
+
 
 async def test_controlling_state_via_topic_with_different_speed_range(
     hass, mqtt_mock, caplog
@@ -285,7 +290,7 @@ async def test_controlling_state_via_topic_no_percentage_topics(
     await hass.async_block_till_done()
 
     state = hass.states.get("fan.test")
-    assert state.state == STATE_OFF
+    assert state.state == STATE_UNKNOWN
     assert not state.attributes.get(ATTR_ASSUMED_STATE)
 
     async_fire_mqtt_message(hass, "preset-mode-state-topic", "smart")
@@ -349,13 +354,17 @@ async def test_controlling_state_via_topic_and_json_message(hass, mqtt_mock, cap
     await hass.async_block_till_done()
 
     state = hass.states.get("fan.test")
-    assert state.state == STATE_OFF
+    assert state.state == STATE_UNKNOWN
     assert not state.attributes.get(ATTR_ASSUMED_STATE)
 
     async_fire_mqtt_message(hass, "state-topic", '{"val":"ON"}')
     state = hass.states.get("fan.test")
     assert state.state == STATE_ON
 
+    async_fire_mqtt_message(hass, "state-topic", '{"val": null}')
+    state = hass.states.get("fan.test")
+    assert state.state == STATE_UNKNOWN
+
     async_fire_mqtt_message(hass, "state-topic", '{"val":"OFF"}')
     state = hass.states.get("fan.test")
     assert state.state == STATE_OFF
@@ -449,7 +458,7 @@ async def test_controlling_state_via_topic_and_json_message_shared_topic(
     await hass.async_block_till_done()
 
     state = hass.states.get("fan.test")
-    assert state.state == STATE_OFF
+    assert state.state == STATE_UNKNOWN
     assert not state.attributes.get(ATTR_ASSUMED_STATE)
 
     async_fire_mqtt_message(
@@ -527,7 +536,7 @@ async def test_sending_mqtt_commands_and_optimistic(hass, mqtt_mock, caplog):
     await hass.async_block_till_done()
 
     state = hass.states.get("fan.test")
-    assert state.state == STATE_OFF
+    assert state.state == STATE_UNKNOWN
     assert state.attributes.get(ATTR_ASSUMED_STATE)
 
     await common.async_turn_on(hass, "fan.test")
@@ -748,7 +757,7 @@ async def test_sending_mqtt_commands_and_optimistic_no_legacy(hass, mqtt_mock, c
     await hass.async_block_till_done()
 
     state = hass.states.get("fan.test")
-    assert state.state == STATE_OFF
+    assert state.state == STATE_UNKNOWN
     assert state.attributes.get(ATTR_ASSUMED_STATE)
 
     await common.async_turn_on(hass, "fan.test")
@@ -883,7 +892,7 @@ async def test_sending_mqtt_command_templates_(hass, mqtt_mock, caplog):
     await hass.async_block_till_done()
 
     state = hass.states.get("fan.test")
-    assert state.state == STATE_OFF
+    assert state.state == STATE_UNKNOWN
     assert state.attributes.get(ATTR_ASSUMED_STATE)
 
     await common.async_turn_on(hass, "fan.test")
@@ -1022,7 +1031,7 @@ async def test_sending_mqtt_commands_and_optimistic_no_percentage_topic(
     await hass.async_block_till_done()
 
     state = hass.states.get("fan.test")
-    assert state.state == STATE_OFF
+    assert state.state == STATE_UNKNOWN
     assert state.attributes.get(ATTR_ASSUMED_STATE)
 
     await common.async_set_preset_mode(hass, "fan.test", "medium")
@@ -1086,7 +1095,7 @@ async def test_sending_mqtt_commands_and_explicit_optimistic(hass, mqtt_mock, ca
     await hass.async_block_till_done()
 
     state = hass.states.get("fan.test")
-    assert state.state == STATE_OFF
+    assert state.state == STATE_UNKNOWN
     assert state.attributes.get(ATTR_ASSUMED_STATE)
 
     await common.async_turn_on(hass, "fan.test")
@@ -1344,7 +1353,7 @@ async def test_attributes(hass, mqtt_mock, caplog):
     await hass.async_block_till_done()
 
     state = hass.states.get("fan.test")
-    assert state.state == STATE_OFF
+    assert state.state == STATE_UNKNOWN
 
     await common.async_turn_on(hass, "fan.test")
     state = hass.states.get("fan.test")