Local Smart Home Guide
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sensor

SONOFF SNZB-04P

SONOFF

budget local: excellentFully controllable on your LAN with no internet dependency. Zigbee
Price
budget band last checked Mar 23, 2026
HA fit
excellent
Works offline
yes
Setup
easy
Hub needed
yes
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SONOFF SNZB-04P, a battery-powered Zigbee door and window contact sensor

Quick verdict

A dead-simple Zigbee contact sensor at a price that lets you put one on every door and window in the house. The P version brings improved range and battery over the original. Pair with a Zigbee coordinator, add to Home Assistant, and automate away — lights on when the front door opens, alerts when the garage is left open, that kind of thing.

Standout: One of the cheapest Zigbee contact sensors on the market, making it practical to cover every door and window.

Notes last checked Mar 23, 2026.

Compatibility snapshot

Home Assistant excellentFull local control, no cloud needed. Native Home Assistant integration or a local protocol.
Apple Home noneNo official support on this platform.
Google Home noneNo official support on this platform.
Alexa noneNo official support on this platform.
Works offline yes
Setup easy
Extra hub needed yes
Power battery

Local control facts

  • Home Assistant: zha integration, Local Polling (home-assistant.io, checked Sep 10, 2026)
  • Zigbee2MQTT: supported device, listed as SONOFF SNZB-04P (Contact sensor) (zigbee2mqtt.io, checked Sep 10, 2026)

Why it stands out

  • among the cheapest Zigbee contact sensors you can find
  • compact enough to fit on most doors and windows without standing out
  • improved battery life and Zigbee range over the older SNZB-04

Reasons to hesitate

  • requires a Zigbee coordinator — no standalone use
  • no built-in temperature sensor (some competitors include one)
  • no native voice assistant support without Home Assistant bridging

Best for

  • Home Assistant users who want to monitor every door and window cheaply
  • triggering automations when doors open — lights, alerts, HVAC adjustments

Avoid if

  • you do not have a Zigbee coordinator
  • you want a contact sensor that works directly with Alexa or Google Home

Privacy and local-control notes

Pure Zigbee device with no cloud component. Fully local when paired with a Zigbee coordinator.

Home Assistant support: supported · integration path: zigbee2mqtt / ZHA.

Buying reality check

Price notes: Rock-bottom pricing for a Zigbee contact sensor. The P version replaces the original SNZB-04 with better range and battery life.

Compare side by side: see sensor comparisons →

Verified against

The compatibility notes above have not been through the source audit yet. The manufacturer's page is here; the notes were last checked Mar 23, 2026.

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