Our engineers teamed up with outside experts to tap the best, most reliable models on today's market.
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It used to be that if your water heater went out, you called in a plumber to replace it with a similar unit, if not the same exact model. That strategy might still make sense, but the category has seen a ton of innovation in recent years, so it’s worth doing some comparison shopping before buying your next water heater, especially since a high-quality unit could be delivering hot water for a few decades.
At the Good Housekeeping Institute, our engineers and outside experts (plumbers, homebuilders, remodeling pros) are constantly testing water heaters, along with other major home systems, like heat pumps and whole-house humidifiers. In recent years, we’ve installed units that pull energy from thin air to heat water at an incredibly energy efficient rate. We’ve also evaluated several tankless water heaters, which have a magic trick of their own, delivering instant hot water at the turn of the knob. Even conventional storage tank water heaters have become more innovative, for example with the addition of a condensing technology that repurposes previously wasted energy, saving big on water heating costs.
In addition to the following roundup of top picks, don't miss our comprehensive buying guide, which drills into the specifics about every kind of water heater available today.
If it's been some years since your last water heater, heat pump technology will probably be new. This A.O. Smith unit shows why it's worth a look. It's known as a hybrid system, because it pairs an air-source heat pump with a conventional electric storage tank water heater. By drawing energy from the ambient air, it's several times more efficient than a standard water heater, saving the typical homeowner close to $600 a year in reduced energy costs. That will offset the steep upfront cost in short order. Plus the high-efficiency water heater is eligible for up to $2,000 in federal tax credits, making the math on this one even better.
The 900 series, available in 50-, 66- and 80-gallon tanks, is also loaded with smart technology, like the Wi-Fi-connected leak detector that will alert you via smartphone app if it springs a leak. That's unlikely given the high-quality construction, including durable copper elements and ceramic fused tank, but the peace of mind is a nice bonus. There’s even a built-in shut-off valve that will automatically turn off the water supply any time a leak is detected.
One thing to keep in mind: as with all heat pump water heaters, the A. O. Smith needs to be installed in an area with at least 1,000 cubic feet of air space so that it has enough available energy to maintain peak operating efficiency.
RELATED: What You Need to Know Before Buying a Heat Pump
While heat pump water heaters represent the category's leading edge, most homeowners still choose to install traditional storage tank water heaters, since they're good value and get the job done. Through years of testing, our experts have been consistently impressed with the overall quality of Rheem water heaters, including this no-nonsense gas model from the Home Depot.
The 50-gallon unit provides plenty of hot water for households with up to five people. With a uniform energy factor, or UEF, of .63, it's far from the most efficient water heater on the market, so don't look for any drop off in energy costs. But our experts say you can expect at least a decade of reliable service, thanks to the water heater's enamel-lined tank and premium anode rod, which protects against rust and corrosion.
Looking for a top value electric storage tank water heater? Rheem's 50-gallon Gladiator has most of the same performance and durability features as its gas counterpart. It costs about $100 more, but that comes with several smart upgrades, including Wi-Fi connectivity for remote operation and monitoring, plus leak detection with automatic shutoff.
Tankless water heaters are another energy-saving technology that’s transforming the category. Besides their superb efficiency, consumers like the fact that they deliver instant hot water (i.e. no standing around in a towel waiting for the shower to heat up).
We recently had the A.O. Smith Signature Series model tested by a pair of outside experts, a Boston-based contractor and Houston-based homebuilder. Both pros gave it perfect marks for ease of installation, performance and overall satisfaction. “The one-gallon-per-minute internal recirculating pump ensures fast delivery of hot water to fixtures,” one noted.
Another feature that impressed our engineers and outside experts alike is the scale-prevention technology, which keeps the system running smoothly without annual descaling by a professional. In the past, this maintenance requirement was a pain point with consumers, since it typically cost about $250 a year, and not doing it could void the manufacturer's warranty. For added peace of mind, A. O. Smith's generous 15-year warranty covers scale-related failures should they occur. Wi-Fi connectivity with companion app enable remote monitoring of the water heater.
RELATED: Good Housekeeping's 2025 Home Renovation Awards
A big advantage of all tankless water heaters is their space-saving design — at roughly the size of a large suitcase, they can be tucked into a closet or mounted high on a wall. This gas-fired unit from Rheem goes one better by enabling the option of outdoor installation, for example mounted to the exterior wall of your home. The Energy Star-qualified water heater boasts an impressive .96 UEF, slashing the typical homeowner's energy costs by close to 40%. It's also eligible for a federal tax credit and many state and local rebate programs, further offsetting its steep upfront cost, relative to traditional storage tank water heaters.
During extensive field tests carried out by one of our outside experts, installation and set up were both straightforward. That's thanks to convenience features like the unit's hanging wall bracket and its compatibility with standard 1/2-inch gas lines. "Another feature that I found highly beneficial is the internal recirculation pump, which ensures fast and efficient delivery of hot water to fixtures throughout the home," our tester noted.
The Rheem water heater is also Wi-Fi-enabled and operated through the brand's EcoNet app. "You can easily adjust the temperature, monitor energy usage in real-time and set the appliance to heat up on a timer," said our tester. The app also provides maintenance reminders, important since the system does need to be drained and flushed regularly to prevent scale buildup.
RELATED: 4 Energy-Efficient Home Improvements for Major Savings
Storage tank water heaters have seen some serious innovation, too. Leading the charge are gas-fired models with condensing technology, which are nearly as efficient as tankless models, thanks to their ability to reuse energy from the exhaust fumes that escape up the flue with traditional units. This 50-gallon water heater from State achieves a .9 UEF, good enough for the Energy Star label, plus generous federal tax credits and state rebates.
State is owned by A.O. Smith Corporation, so it brings a lot of the same performance and reliability. It’s the go-to brand for many plumbing professionals, who like its 75-year track record. Many of the high-tech features our experts see on A. O. Smith water heaters are evident on this condensing gas model too, including leak detection sensors that alert if a leak occurs.
Condensing technology used to be exclusive to extra-large storage tank heaters — up over 60 gallons in most cases. In addition to this 50-gallon unit, State also has carries a 40-gallon version, good for smaller households with two to three people.
I've been testing and writing about water heaters for close to 25 years. In that time, I've become familiar with all major brands in the category, so I know which ones have the best track records in terms of quality and reliability. I've also spearheaded numerous investigative reports on the topic of energy and water efficiency, working closely with outside experts from government, industry and the home services space.
As Director of Home Improvement & Outdoor at the Good Housekeeping Institute, I oversee water heater testing in our Lab, as well as the continuous in-home, survey-based consumer testing that allows us to evaluate these devices in real-world conditions.
For this water heater round up, our team pulled together insights from trade shows and industry events, like the International Builders' Show, and interviewed various experts from the field. We also drew on our hands-on experience overseeing the installation of several water heaters in the homes of expert testers as part of our annual Home Renovation Awards.
Having written thousands of product reviews and how-to articles on all aspects of home ownership, from routine maintenance to major renovations, Dan (he/him) brings more than 20 years of industry experience to his role as the director of the Home Improvement & Outdoor Lab at the Good Housekeeping Institute. A one-time roofer and a serial remodeler, Dan can often be found keeping house at his restored Brooklyn brownstone, where he lives with his wife and kids.
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