ThirdReality Door Sensor

Quick verdict

The ThirdReality Door Sensor is a straightforward Zigbee contact sensor that prioritizes reliability and price over extras. For entry alerts, auto-lock routines, and occupancy logic, it gives Home Assistant users dependable open/close state updates without cloud dependence.

Standout: Low-cost Zigbee contact sensing that scales well across many doors and windows.

Notes last checked May 31, 2026.

Compatibility snapshot

Why it stands out

• extremely affordable and great for covering every door and window
• reliable open/close detection with solid Zigbee support
• long battery life on 2x AAA batteries (up to 2 years)

Reasons to hesitate

• no temperature or lux sensor like some pricier alternatives
• requires a Zigbee coordinator
• plastic build feels cheap, though it holds up fine

Best for

• blanketing your home with door and window sensors on a budget
• Zigbee-based Home Assistant setups needing basic contact sensors

Avoid if

• you want a multi-sensor (contact + temperature + lux) in one device
• you have no Zigbee coordinator

Privacy and local-control notes

Runs locally over Zigbee with no required cloud account. Open/close telemetry can stay entirely on your local hub and automation server.

Home Assistant support: supported · integration path: ZHA / Zigbee2MQTT.

Buying reality check

Price notes: One of the best value picks in Zigbee contact sensors, especially when purchased in multi-packs.

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