A burst pipe or water leak is one of the biggest threats to homeowners, potentially causing thousands of dollars of damage. Not only will you have to repair the leak, but you'll have to contend with replacing walls, mitigating mold, and throwing out lots of waterlogged items.
One of the best water leak detectors can help prevent this from happening by sensing temperature and water leaks, and alerting you if anything is wrong — before it becomes a major problem.
There are two types of water leak detectors in this guide: Water leak detectors without shutoff valves, and water leak detectors with shutoff valves.
The first are sub-$100 devices that you place near pipes, water heaters, and other places where you're likely to get a leak. If they sense water, they'll send you an alert, but it'll be up to you to manually turn off your water.
Based on our research, our favorite model among this type of water leak detector is the Flo by Moen Smart Water Detector. In addition to leaks, it can also measure the humidity levels as well as the temperature — important to know if your basement or other area is in danger of freezing. It can warn you in the app and emits an 85-decibel alarm when it detects water. And, if you decide to upgrade to a Moen water leak detector that can shut off your water automatically, this sensor can be linked to it.
The second type of water leak detector — the one with a built-in shutoff valve — costs upwards of $400 and needs to be professionally installed, but in the event of a leak, it can automatically shut off the water coming into your home. These models can also monitor the flow of water through your pipes to detect leaks behind your walls and recommend ways to conserve water — and lower your utility bill. It's one of the best smart home gadgets that could save you money.
For this, we like the Flo by Moen, which can fit three sizes of water lines, and can show you your water usage by fixture. The FloProtect service ($5/month) adds professional monitoring and live-chat support, and will cover the cost of your deductible (up to $5,000) if there's water damage.
You'll also want to check out these 15 water saving tips to lower your bill.
The best water leak detectors you can buy today
Why you can trust Tom's Guide Our writers and editors spend hours analyzing and reviewing products, services, and apps to help find what's best for you. Find out more about how we test, analyze, and rate.
Best overall
If you're not ready to commit to a water-shutoff system, the Flo by Moen Smart Water Detector is a good place to start. This device senses leaks, temperature, and humidity, and can emit an 85-decibel alarm when it detects water. It also connects to the Flo by Moen app, where you can link it with Alexa, Google Assistant, and other smart home systems.
This device comes with the main unit as well as a four-foot cable, so you can mount it on the wall, and not worry about it getting washed away if you get a flood. And, when you want to step up to a system that can also shut off your water, you can link it to the Flo by Moen shutoff valve.
Loudest alarm
Many pipes will burst when the water trapped inside them freezes and expands. That's why, in addition to water leaks, this Resideo (a division of Honeywell) sensor can also detect temperature changes and humidity, and send you an alert when things get too cold. The Lyric sensor runs on two AA batteries, which are rated to last up to three years. It includes a 4-foot cable, the entire length of which can detect leaks.
When the sensor detects a leak, it sends an alert to your phone and emits a 100-dB alarm. It also connects directly to your Wi-Fi — no hub needed. Resideo's products also work with a wide range of smart-home systems.
Smartest water leak detector
For those whom the Phyn Plus Smart Water Assistant + Shutoff valve is too expensive, the Phyn Smart Water Assistant could be the answer. This device, which costs less than half the price, does everything the Phyn Plus does, except for having an automatic shutoff valve.
Like the Phyn Plus, the Phyn senses the water pressure in your home, can detect when there's a drop in pressure and using algorithms, can let you know if it's being caused by a burst pipe or just a leaky toilet. Because it doesn't include a shutoff valve, the Phyn can be easily installed by a homeowner, under any sink. The one caveat is that you'll also need a power source nearby. But, the Phyn could save you money over the long haul, even if you don't have a major catastrophe.
Most sensors
The D-Link Wi-Fi Water Leak Sensor and Alarm Starter Kit works a little differently than other water leak detectors. A Master Sensor, which needs to be plugged into a wall, acts as a hub between wireless remote sensor pods and your home Wi-Fi network. (You can connect up to 16 pods.) Each pod costs $24 each, and is powered by two AAA batteries which the company says will last up to five years before needing to be replaced.
The main sensor pod has a loud 100dB alarm, a strobe light, and can send an alert not just to your smartphone, but to any connected Google Home smart speakers. Pretty neat.
Best water leak detector with shutoff valve
The Flo by Moen monitors your water flow and can automatically shut off your water if it detects a major leak. In addition, the Flo checks your water pressure and temperature, and its app shows you how much water you're using per day. It also tells you what's using water, and it runs daily tests to determine if there's a water leak.
All users now get an Insurance Verification Letter, as well as the ability to see your water usage by fixture. If you opt for the FloProtect service ($5/month), you can get monitoring and live-chat support. FloProtect will also cover the cost of your deductible (up to $5,000) if there's water damage. The company also increased the length of its warranty to three years.
The Flo by Moen comes in three sizes, so it's compatible with 3/4 inch, 1-inch, and 1.25-inch water lines. Customers can purchase an optional battery backup ($249), which will provide up to three days of protection if power gets shut off.
Best no-subscription shutoff valve
Not only can the Phyn Plus Smart Water Assistant alert you if there's a leak, but it can also automatically shut off the water coming into your home, which is why it's the best water leak detector with a shutoff valve. This second-generation Phyn Plus is 25% smaller than the original model, so it should be easier to fit into tighter spaces. It's also about $200 less expensive, too.
Phyn's super-smart water assistant has a series of blue LEDs along one edge that give the illusion of flowing water. Inside the device is a water-flow sensor, as well as some interesting algorithms that can detect leaks throughout your house based on water pressure. It can even tell the difference between a toilet flushing and a drip from a faucet, and give you insights into how much water you're using. So, you don't need to install remote sensors throughout your house.
The Phyn Plus can be installed indoors or outdoors, and works with Alexa, Google Assistant and IFTTT. Unlike the Flo by Moen, there are no additional subscription fees. However, it has to be plugged in to work, and there's no battery backup.
Easiest to install
The Flume 2 Smart Home Water Monitor & Water Leak Detector straps around your water line — no plumber necessary — and connects to a Wi-Fi bridge to tell you based on the water flow and pressure if there's a leak somewhere in your home.
More than that, the Flume 2 can also analyze your water usage. Flume also removed its subscription fees, so you can get more granular data on specific appliances and faucets, and help you create daily and weekly budgets for water consumption. It can also provide indoor vs. outdoor water use, let you set up custom alerts, and gives you 15% off leak repair services from Angi.
Sump pump monitor
One of the best ways to prevent your basement from flooding is to install a sump pump — but what happens if the sump pump fails and you don't know about it? The Moen Smart Sump Pump Monitor isn't a water leak detector per se, but it will keep tabs on your sump pump and alert you if it thinks anything is amiss. The monitor comes with a 10-foot smart sensor that monitors the water level in the sump area, a 6' Remote Leak Sensing Disc, and a 9-Volt battery that sounds an alarm if the power goes out.
In addition to water levels, the monitor also checks humidity levels — to warn you of any potential mold issues — and the temperature around the sump pump to alert you to any freeze warnings. And all you have to do is to plug it into your sump pump.
What to look for when buying a water leak detector
Water leak detectors fall generally into two categories: those which can shut off your water, and those that can’t. The latter are generally inexpensive — less than $100 — and will send an alert to your smartphone when they sense water. However, it's then up to you to turn off your water, which can be a problem if you're not at home. Those that have shutoff controls typically cost upward of $400 and require a plumber to install, but could be worth the investment, as they'll not only help reduce catastrophic damage, but can also help lower your monthly insurance bill.
Regardless of the type of water leak detector you purchase, here are a few things you need to consider before you buy.
Do you want something that can shut off your water?
While all water leak detectors will (or should) alert you when there's a water leak, only some will also take the next step of shutting off your main water supply, to limit the amount of water that leaks out. These models, though, often cost more than $400, and must be professionally installed, unless you're really handy with plumbing. However, some insurance companies will lower your deductible if you have one installed, which can defray the cost over time.
Do you want to monitor your water usage?
Because of climate change, some areas of the country are experiencing water shortages, and are seeing their water rates go up as well. If you want to be more conscious of how you're using your water — or simply want your bill to go down — some water leak detectors can tell you which of your appliances and faucets account for the most water use.
Battery or plug-in?
Some water leak detectors run on batteries, while others need to be plugged in; the former type makes it easier for the detectors to fit into locations that are far from an outlet, but their batteries will need to be replaced every year or so.
Do you want a built-in alarm?
A detector with a built-in alarm will sound a siren, so that you can hear where the leak is coming from, without needing your smartphone. This is a really handy feature, and one we recomment.
Smart-home integration
While not a necessity, if a water leak detector works with other smart- home systems, such as Alexa or Google Home, you can program a routine to have a light flash in your house when there's a water leak, or increase the temperature if there's a risk of water lines freezing.
If you detect a leak, you'll want to get it repaired as soon as possible as it can make a huge impact on your bills. Check out these 9 ways you could be wasting water and not know it.
Common sources of water leaks
Once you purchase a water leak detector, you'll want to place them in the areas most likely subject to water leaks. These can include the following:
- Hot water heater
- Toilets
- Sink drains
- Washing machine
- Dishwasher
Place the water leak detector near the base of the items listed above; that way, if there's a leak from a drain or your toilet, the water will hit the detector before anything else.
Many times, leaks can occur when a pipe gets clogged and water backs up, which is why it's important to know how to unclog a shower drain and how to unclog a toilet to prevent this from happening in the first place.
You should also keep in mind that leaks can occur in places where it's hard to put a water leak detector, such as pipes in your wall, in your basement, or leading to an outdoor faucet.
Plumbing tips and tricks
While they can be live savers, plumbers aren't necessarily the cheapest expense, so it's good to know how to make some simple repairs yourself. Here are a few plumbing-related how-tos, so you can save yourself a few bucks. Of course, if you're ever unsure, consult a professional.
- How to fix a leaky bathtub faucet
- How to winterize your sprinkler system
- How to bleed a radiator
- How to unclog a shower drain
More from Tom's Guide
