Shelly Flood Gen4

Quick verdict

The Flood Gen4 is unusually flexible: one leak sensor that can run on WiFi, Zigbee or Matter depending on your setup, all locally in Home Assistant with no cloud. The included leak cable detects water along its length, which beats a single contact point. A strong, affordable pick for leak protection on a local-first network.

Standout: Multi-protocol leak sensor (WiFi, Bluetooth, Zigbee, Matter) with an extendable leak detection cable, fully local.

Last checked: 2026-05-25

Compatibility snapshot

Why it stands out

• flexible protocols: WiFi, Bluetooth, Zigbee and Matter on one device
• includes a leak sensor cable that detects water along its full length, not just one point
• fully local through the native Shelly integration or Matter, no cloud needed

Reasons to hesitate

• battery powered, so it reports on intervals rather than instantly when idle
• you must pick one radio mode per device, configured at setup
• Matter water leak support in Home Assistant is newer than WiFi Shelly support

Best for

• protecting water heaters, washing machines and under-sink areas with local leak alerts
• Home Assistant users who want a leak sensor that fits WiFi, Zigbee or Matter setups

Avoid if

• you need a hardwired, always-on sensor with instant reporting
• you want a purely Zigbee-mesh sensor and do not want to manage WiFi or Matter pairing

Privacy and local-control notes

Gen4 sensor supporting WiFi, Bluetooth, Zigbee and Matter. Works locally through the native Home Assistant Shelly integration or via Matter, with no Shelly Cloud account required.

Home Assistant support: supported · integration path: Shelly (native / local) or Matter.

Buying reality check

Price notes: Budget pricing around the low thirties USD. Includes a leak sensor cable in the box.

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