# Shelly Flood S Gen4

Shelly Flood S Gen4 is a direct Matter-over-Wi-Fi flood sensor for Shelly-heavy homes. The safer expectation is Matter for the shared endpoint and Shelly for firmware, diagnostics, and any detailed device settings.

Canonical page: https://matterhome.io/devices/shelly-flood-s-gen4
Markdown page: https://matterhome.io/devices/shelly-flood-s-gen4.md
Author: Matterhome Editorial Team
Author profile: https://matterhome.io/authors/matterhome-editorial-team
Edited and fact-checked by: JC Martinez
Editor profile: https://matterhome.io/authors/jc-martinez

## Device Facts

- Brand: Shelly
- Model: Flood S Gen4
- Product type: Matter-over-Wi-Fi Flood Sensor
- Category: Sensors
- Connection: Matter over Wi-Fi
- Matter status: CSA lists Shelly Flood S Gen4 as a Matter 1.3 product using Wi-Fi, Bluetooth, certified on 2025-06-30.
- Launch date: 2025-06-30
- Thread border router required: No
- Brand hub required: No
- Typical price range: €15-€40
- Review status: Compatibility guide
- Product image: https://matterhome.io/content-assets/devices/shelly-flood-s-gen4/product.png
- Product image alt text: Shelly Flood S Gen4 product image
- Product image source: https://cdn.shopify.com/s/files/1/0871/9967/8813/files/Shelly-Flood-S_main-image.png?v=1776239045

## Ecosystem Support

- Apple Home: Limited
- Google Home: Limited
- Alexa: Limited
- SmartThings: Limited
- Home Assistant: Limited

## Best For

- Water-risk spots where Wi-Fi is reliable
- Shelly homes that want Matter-visible alerts
- Buyers who will test alert behavior before trusting it

## Skip If

- Wi-Fi is weak at the leak-risk location
- You need a professionally monitored safety system
- Your ecosystem cannot use the alert state you need

## Setup Notes

- Place it where Wi-Fi coverage is reliable.
- Test the alert state in the Matter ecosystem before relying on it.
- Keep Shelly available for firmware and sensor settings.

## Known Limitations

- Alert states and notifications should be tested in the target ecosystem.
- Shelly app or web UI may still be needed for firmware, setup, diagnostics, and advanced behavior.
- Local Wi-Fi reliability still determines the normal Matter connection path.

## Pros

- Direct Matter-over-Wi-Fi sensor listing
- No Thread border router required
- Can share alerts with Matter ecosystems
- Shelly app can handle firmware and device settings

## Cons

- Alert handling can vary by ecosystem
- Wi-Fi coverage matters at the sensor location
- Shelly app is still needed for firmware and settings

## Sources

- https://csa-iot.org/csa_product/shelly-flood-s-gen4/
- https://www.shelly.com/products/shelly-flood-s-gen4
- https://cdn.shopify.com/s/files/1/0871/9967/8813/files/Shelly-Flood-S_main-image.png?v=1776239045

## Direct Matter without a Shelly hub

Shelly Flood S Gen4 is listed by CSA as a Matter over Wi-Fi device. That makes the Matter path direct: it joins a Matter controller over Wi-Fi and does not need a Thread border router or a Shelly bridge for the Matter endpoint.

## Setup path

Place and test the sensor before trusting the alert path. A flood sensor is only useful if the alert reaches the app or automation you expect.

Use Shelly's app or web interface for Wi-Fi onboarding, firmware, device settings, calibration, and any device detail that your Matter ecosystem does not expose cleanly.

## What to verify

Matter should cover the common endpoint, but the valuable details can vary. For Shelly meters, plugs, and PM relays, verify wattage, energy totals, and reporting frequency. For flood and motor-control devices, test the exact alert or movement behavior before building routines around it.

## Should you buy it?

Buy Flood S Gen4 when the physical format fits the job and you want a direct Wi-Fi Matter path. Skip it if you need every Shelly app feature to appear identically in Apple Home, Google Home, Alexa, SmartThings, and Home Assistant.