diff --git a/source/_integrations/binary_sensor.mqtt.markdown b/source/_integrations/binary_sensor.mqtt.markdown index ef9b3d92de8..2ce84fdea51 100644 --- a/source/_integrations/binary_sensor.mqtt.markdown +++ b/source/_integrations/binary_sensor.mqtt.markdown @@ -8,9 +8,9 @@ ha_iot_class: Configurable ha_domain: mqtt --- -The `mqtt` binary sensor platform uses an MQTT message received to set the binary sensor's state to `on` or `off`. +The `mqtt` binary sensor platform uses an MQTT message received to set the binary sensor's state to `on`, `off` or `unknown`. -The state will be updated only after a new message is published on `state_topic` matching `payload_on` or `payload_off`. If these messages are published with the `retain` flag set, +The state will be updated only after a new message is published on `state_topic` matching `payload_on`, `payload_off` or `None`. If these messages are published with the `retain` flag set, the binary sensor will receive an instant state update after subscription and Home Assistant will display the correct state on startup. Otherwise, the initial state displayed in Home Assistant will be `unknown`.