Shelly Flood Gen4 vs Third Reality Water Leak Sensor comparison

Updated July 2026

Data from Amazon and official Shelly and Third Reality sites.

2026 verdict

The Shelly Flood Gen4 leads this water leak sensor comparison against the Third Reality Water Leak Sensor on several fronts: a higher owner rating, a longer warranty, weather resistance, wider connectivity and integrations spanning WiFi, Zigbee, Bluetooth and Matter, plus more supported sensors, alerts and an on-device alert light. The Third Reality Water Leak Sensor answers with a lower price and a longer battery life, keeping it the more budget-friendly, longer-lasting Zigbee option. Buyers who want the best-rounded, most connected sensor with the longest warranty should choose the Shelly Flood Gen4; those chasing the cheapest, longest-lasting Zigbee sensor should pick the Third Reality Water Leak Sensor.

Feature	Shelly Flood Gen4	Third Reality Water Leak Sensor	Winner
Price	$39.99	$20.99	Third Reality Water Leak Sensor
Rating	4.2	4.1	Shelly Flood Gen4
Warranty	3 years	1 year	Shelly Flood Gen4
Weather Resistance	IP44	NO	Shelly Flood Gen4
Battery Life	2 years	3 years	Third Reality Water Leak Sensor
Connectivity	2.4 GHz WiFi, Bluetooth, Zigbee	Zigbee	Shelly Flood Gen4
Integrations	Google Home, Alexa, Apple HomeKit, Samsung SmartThings, Home Assistant, Matter	Google Home, Alexa, Apple HomeKit, Home Assistant	Shelly Flood Gen4
Sensors	Water Leak, Temperature	Water Leak	Shelly Flood Gen4
Alerts	Water Leak Alerts, Temperature Alerts, Freeze Temperature Alerts	Water Leak Alerts, Low Battery Alerts	Shelly Flood Gen4
On Device Alert Light	YES	NO	Shelly Flood Gen4
On Device Alert Sound	YES	YES	Tie

Winner

Shelly

Shelly Flood Gen4

$39.99

Buy on Amazon USA

+ Rating: 4.2
+ Warranty: 3 years
+ Weather Resistance: IP44
- Price: $39.99 vs $20.99
- Battery Life: 2 years vs 3 years

Third Reality

Third Reality Water Leak Sensor

$20.99

Buy on Amazon USA

+ Price: $20.99
+ Battery Life: 3 years
- Rating: 4.1 vs 4.2
- Warranty: 1 year vs 3 years

Frequently Asked Questions

Which is better overall: Shelly Flood Gen4 or Third Reality Water Leak Sensor?

The Shelly Flood Gen4 wins overall on rating, warranty, weather resistance, connectivity, integrations, and sensor and alert coverage. The Third Reality Water Leak Sensor remains cheaper and lasts longer on its battery.

What is the biggest difference between the Shelly Flood Gen4 and the Third Reality Water Leak Sensor?

Protocol breadth versus price and runtime. The Shelly Flood Gen4 supports WiFi, Zigbee, Bluetooth and Matter with weather resistance and an alert light, while the Third Reality Water Leak Sensor is a cheaper, longer-lasting Zigbee-only sensor.

Which one has an on-device alert light?

Only the Shelly Flood Gen4. It has both a built-in buzzer and an LED indicator, while the Third Reality Water Leak Sensor has an alarm sound but no light indicator.

Which one has the longer battery life?

The Third Reality Water Leak Sensor is rated to last longer between battery changes than the Shelly Flood Gen4.

Who should buy the Shelly Flood Gen4?

Buyers who want the better-rated, longer-warrantied, most connected sensor with weather resistance and a visual alert.

Who should buy the Third Reality Water Leak Sensor?

Buyers who want the cheaper, longer-lasting Zigbee sensor and don't need Matter, Bluetooth or WiFi support.

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