Short version: The SONOFF SNZB-04PR2 is a small, battery-powered sensor designed to tell you if a door or window is open or closed. It uses Zigbee, a common wireless standard for smart home devices, to connect directly to Home Assistant. The main thing to remember is that you will need a Zigbee coordinator, which is a USB stick or device that lets Home Assistant talk to Zigbee devices.
Updated November 2026.
What the SONOFF SNZB-04PR2 Zigbee door sensor is
The SONOFF SNZB-04PR2 is a door and window sensor. Its main job is to detect when a door or window is opened or closed. This can be useful for security, automating lights, or simply knowing if something is left ajar. The listing says it comes with two parts: a main sensor unit and a smaller magnet. When these two parts are separated, the sensor reports that the door or window is open. When they are together, it reports closed.
This device is powered by a CR2032 coin cell battery, which is a common type of small, round battery. Zigbee devices like this are known for their long battery life, often lasting a year or more, because they use very little power. It communicates using Zigbee, which is a wireless protocol that creates its own mesh network. This means that if you have other Zigbee devices that stay powered on, they can help extend the signal range for devices like this sensor.
A key feature of the SNZB-04PR2 is its tamper alert. If someone tries to remove the sensor from where it is mounted, it can send an alert. This adds an extra layer of security, letting you know if the sensor itself is being interfered with.
Home Assistant compatibility
The SONOFF SNZB-04PR2 is designed to work well with Home Assistant, providing local control. This means it does not need to connect to SONOFF’s cloud servers or any internet service to function once it is set up with Home Assistant. You will need a Zigbee coordinator connected to your Home Assistant server to make it work.
| Option | Works? | Notes |
|---|---|---|
| ZHA | Yes | ZHA is Home Assistant’s built-in way to manage Zigbee devices. |
| Zigbee2MQTT | Yes | Zigbee2MQTT is another popular add-on that connects Zigbee devices to Home Assistant. |
| Tuya (cloud integration) | No | This is a native Zigbee device, not a Wi-Fi device that uses the Tuya cloud. |
| Matter | No | Zigbee is a different standard than Matter. This sensor does not support Matter directly. |
| Local or cloud | Local | Works entirely within your home network after setup, without needing the internet. |
Who it is for
This sensor is a good fit for Home Assistant users who already have a Zigbee network set up with a coordinator. It is ideal if you want simple, reliable open/close detection for doors, windows, or even cabinets. If you prioritize local control, meaning your devices work without needing an internet connection or a manufacturer’s cloud, then this sensor is a strong candidate. Its tamper alert feature also makes it appealing for those looking to add basic security monitoring.
You might want to skip this sensor if you do not have a Zigbee coordinator and prefer to use Wi-Fi or Matter devices. If you are looking for more advanced presence detection, like knowing if someone is in a room even if a door is closed, you would need a different type of sensor, such as a mmWave presence sensor. This sensor is purely for open/close status.
How to set it up in Home Assistant
Setting up the SONOFF SNZB-04PR2 with Home Assistant using ZHA is a straightforward process, assuming you already have your Zigbee coordinator configured. Here are the steps:
- First, make sure your Zigbee coordinator is plugged into your Home Assistant server and that the ZHA integration is already set up in Home Assistant.
- Open your Home Assistant interface in a web browser.
- Go to Settings, then click on Devices & services.
- Find your ZHA integration card and click on Configure.
- On the ZHA page, look for the Add device button and click it. This will put your Zigbee network into pairing mode.
- Now, take your SONOFF SNZB-04PR2 sensor. You will usually find a small button on the side or back. Press and hold this button for about 5 seconds until the LED indicator on the sensor starts to blink, which means it is in pairing mode.
- Home Assistant should soon detect the new device. Once it appears, you can give it a name, assign it to a room, and finish the setup. The sensor will then show up as an entity in Home Assistant, reporting its open/close state and battery level.
Common issues and variants to avoid
- Wi-Fi vs. Zigbee versions: SONOFF makes many smart home devices, and some look very similar but use Wi-Fi instead of Zigbee. Always double-check the product listing and the box to ensure you are buying the Zigbee version (SNZB-04PR2) if you intend to use it with your Zigbee network in Home Assistant. Listings sometimes mix different models.
- Pairing problems: If the sensor does not pair on the first try, try moving it closer to your Zigbee coordinator or a strong Zigbee repeater. You may also need to reset the sensor by holding the pairing button for a longer time (sometimes 10 seconds or more) or removing and reinserting the battery before trying to pair again.
- Battery life and reporting: While Zigbee sensors generally have long battery life, the actual duration can vary. Home Assistant will report the battery level, but sometimes this update can be slow. If you notice strange behavior, checking or replacing the CR2032 battery is a good first step.
- Zigbee mesh range: Like all wireless devices, Zigbee sensors have a limited range. If your sensor is far from your Zigbee coordinator or other always-on Zigbee devices (like smart plugs or light bulbs that act as repeaters), you might experience connection issues. Consider adding more Zigbee routers to strengthen your Zigbee mesh network.
Should you buy it?
The SONOFF SNZB-04PR2 Zigbee Door/Window Sensor is a reliable and affordable option for Home Assistant users looking for simple, local open/close detection. Its direct compatibility with ZHA and Zigbee2MQTT, along with its tamper alert, makes it a solid choice for basic security and automation. If you already have a Home Assistant setup with a Zigbee coordinator, this sensor is an easy recommendation.
For those who do not have a Zigbee setup yet, you will need to invest in a Zigbee coordinator first. If you need more advanced sensing capabilities, such as detecting human presence in a room regardless of door state, you might want to explore alternatives like mmWave presence sensors, but for simple contact detection, the SNZB-04PR2 performs its role well.
Frequently Asked Questions
Does the SONOFF SNZB-04PR2 work with Home Assistant without the cloud?
Yes, the SONOFF SNZB-04PR2 is a Zigbee device that can connect directly to Home Assistant using a Zigbee coordinator. This allows it to work entirely locally, meaning it does not need an internet connection or SONOFF’s cloud services once it is set up.
Do I need a hub for the SONOFF SNZB-04PR2?
Yes, you need a Zigbee coordinator, often called a Zigbee hub or stick, to use the SONOFF SNZB-04PR2 with Home Assistant. This device acts as a bridge, allowing Home Assistant to communicate with the Zigbee sensor. It is not a separate brand-specific hub, but a universal Zigbee coordinator.
Is the SONOFF SNZB-04PR2 a Zigbee or Wi-Fi version?
The SONOFF SNZB-04PR2 is specifically a Zigbee version. SONOFF makes both Zigbee and Wi-Fi devices, so it is important to check the model number and product description to ensure you are getting the correct Zigbee variant for your Home Assistant setup.