5 Best Water Heaters (2025)

Water heaters are essential appliances that provide hot water for various household needs, from showers to dishwashing. They come in different types, sizes, and fuel options, each with its own set of advantages. The key to selecting the right water heater is understanding your household’s hot water demands and balancing that with energy efficiency and budget considerations.

When choosing a water heater, it’s important to look beyond just the upfront cost. Factors such as energy efficiency, fuel type, and maintenance requirements can significantly impact the long-term expenses and performance of your unit. Additionally, considering the installation space and local building codes is crucial for a successful setup.

Here are our picks for the top water heaters on the market.

Best Overall

Stiebel Eltron Electric Tankless Water Heater

4.5/5

Go

Best Tankless Gas Heater

Rinnai Tankless Gas Water Heater

4.4/5

Go

Best Point-of-Use Heater

Bosch Electric Mini-Tank Water Heater

4.3/5

Go

Top 5 Water Heaters

*Links open to product retail page.

• Best Overall: Stiebel Eltron Electric Tankless Water Heater
• Best Tankless Gas Heater: Rinnai Tankless Gas Water Heater
• Best Point-of-Use Heater: Bosch Electric Mini-Tank Water Heater
• Most Energy Efficient Heater: EcoSmart Tankless Electric Water Heater
• Best Portable Heater: GASLAND Portable Gas Water Heater

Best Overall

Courtesy Amazon

Stiebel Eltron Electric Tankless Water Heater

• $624
• $698
• 11% off

Prices taken at time of publishing.

This electric tankless water heater has a sleek, space-saving design, giving you hot water without being intrusive or unsightly. It uses Stiebel Eltron’s Advanced Flow Control technology to maintain the water temperature you selected using the dial.

• $624 at Amazon

Pros and Cons

✔ Has an electric, tankless water heater design
✔ Operates with a maximum flow rate of 5 gallons per minute (GPM)
✔ Comes with a seven-year leak warranty and 3-year parts warranty

✘ Is the most expensive water heater in this review
✘ Some customers who use well water had issues with the heater

What Customers Are Saying

Happy customers mentioned easy installation, reduced energy costs, and simple temperature control. However, some users were disappointed when it didn’t make their water as warm as they wanted.

Best Tankless Gas Heater

Courtesy Amazon

Rinnai Gas Tankless Hot Water Heater

• $765
• $857.48
• 11% off

Prices taken at time of publishing.

For those who want a permanent gas water heater, consider this tankless model. It uses less energy by heating water on demand. Once you activate it, it warms up to 6.5 gallons of water per minute to run your dishwasher, shower, washing machine, and more at once.

• $765 at Amazon

Pros and Cons

✔ Has a tankless design powered by natural gas
✔ Operates with a maximum flow rate of 7.5 GPM
✔ Comes with a 10-year heat exchanger warranty, 5-year labor warranty, and 1-year parts warranty

✘ The unit works harder than necessary if your local groundwater temperatures are colder than average
✘ The module for WiFi control isn’t included

What Customers Are Saying

Users were happy with this water heater’s efficient temperature control, high water pressure, and non-invasive design. The small selection of customers who left negative reviews struggled with installation, as it required an unusual venting system.

Best Point-of-Use Heater

Courtesy Amazon

Bosch Electric Mini-Tank Water Heater

• $285.99

Prices taken at time of publishing.

If the water heater in your basement struggles to warm the water coming from your upstairs sink, consider this point-of-use model. It connects to a water line, plugs into a wall outlet, mounts under a sink to give you four gallons of instant hot water when you’re washing your hands.

• $285.99 at Amazon

Pros and Cons

✔ Has an electric design
✔ Holds up to 4 gallons of water
✔ Comes with a 6-year tank warranty and 2-year parts warranty

✘ Doesn’t have a digital temperature display
✘ Has a limited range compared to full-size water heaters

What Customers Are Saying

Those who were pleased with this water heater mentioned its easy setup and affordable price. They also said that it heated water instantly and effectively. However, unhappy users wrote that the heater was prone to leaking.

Most Energy Efficient Heater

Courtesy Amazon

EcoSmart Electric Tankless Water Heater

• $400.31

Prices taken at time of publishing.

Small but mighty, this electric tankless water heater takes up 12 cubic feet of space on your wall and warms up to 6.5 gallons of water per minute. Because it’s not constantly warming water in a tank, it can reduce your electricity costs by up to 50%.

• $400.31 at Amazon

Pros and Cons

✔ Has an electric, tankless design
✔ Operates with a maximum flow rate of 6.5 GPM
✔ Comes with a lifetime warranty

✘ Some customers reported issues with warranty validation
✘ The warranty doesn’t extend to any applicable labor costs

What Customers Are Saying

Positive reviews said that this water heater lasted several years, heating a lot of water efficiently. When customers did have issues with longevity, they struggled to get the manufacturer to cover the repairs with the warranty.

Best Portable Heater

Courtesy Amazon

GASLAND Portable Gas Water Heater

• $169.99
• $189.99
• 11% off

Prices taken at time of publishing.

You can use this water heater at a campsite, in an RV, in a greenhouse, or anywhere else where you need hot water on the go. To provide reliable, on-demand heated water, it has overheating and anti-freezing protection built-in, plus a flame-viewing window.

• $169.99 at Amazon

Pros and Cons

✔ Has a gas, tankless design
✔ Has water heater safety features, including dry combustion and low water flow detection
✔ Includes a detailed instruction manual and necessary hardware

✘ Although it can be used indoors, it’s primarily designed for outdoor use only
✘ Some customers said that the water didn’t get hot enough

What Customers Are Saying

Users who gave this portable water heater four- and five-star ratings said that the unit was lightweight, easy to install, and the controls were simple to operate. Conversely, some reviewers said that the unit was susceptible to freezing, despite its built-in anti-freezing protection.

Hot Water Heater Sizes

Even if you were happy with the old tank, don’t automatically assume it had a suitable heating capacity. To determine that capacity, you first need to add up how much hot water your household uses during the busiest hour of an average day.

“Size a water heater for your demand 363 days a year, not the one or two days that you’ve got 25 relatives visiting,” says Richard Trethewey, This Old House plumbing and heating expert. “Otherwise, you’ll end up with an energy-gobbling beast in the basement.”

This sum—your household’s “peak-hour demand” for hot water — should be close to your water heater’s “first-hour rating” (FHR) printed on each heater’s yellow Energy Guide label. The FHR tells you how many gallons of hot water a heater can produce during an hour of high usage. (It is not the same as the number of gallons a tank can hold.)

Assessing Hot Water Heater Efficiency

The following number to look at is the energy factor (EF), representing the percentage of energy that is turned into hot water by that specific model. The higher the number, the more efficient the unit and the less it will cost to operate. (An EF of 1 would indicate that 100 percent of the energy a heater uses is converted into hot water—a physical impossibility, alas.)

While a high EF is good, you have to factor in the cost of the energy the heater uses to get an accurate picture of how much it costs to operate. In most areas, for example, an electric heater with an EF of 0.8 will cost more to run than a similar-size gas model with an EF of 0.6 due to the higher price of electricity compared with gas.

In most cases, water heaters with high EFs cost more to buy but don’t overlook the potential long-term savings in fuel costs. Here’s an easy formula to calculate the payback period when comparing heaters with the same FHR rating but different prices: Divide the difference between the prices of the two models by the difference between their estimated annual operating costs (printed on the Energy Guide labels). The result is the number of years it will take the energy savings to offset the higher purchase price. Look for a payback within ten years, the expected life span of an average heater. Of course, if energy prices go up during that time, the payback period will be shorter.

Keep in mind that the estimated annual operating cost is just an approximation. To more accurately predict performance and payback time, plug each model’s EF and your actual energy cost into the online worksheets provided by the Air-Conditioning, Heating, and Refrigeration Institute (AHRI).

Comparing Types of Hot Water Heaters

When comparing the different types of heaters, you’ll see that gas and oil-fired units generally have higher FHRs, relative to their tank size than electric models. (Flames heat water more quickly than heating elements do.) If you come up with a high FHR on your worksheet, say 100 gallons or so, you may need to install a second water heater.

Storage Tank Water Heaters

Storage tank water heaters are the most common type found in homes. They consist of an insulated tank that holds and heats water until it’s needed. These units are available in various sizes and can be powered by electricity, natural gas, or oil.

Pros:

• Lower upfront cost
• Simple installation
• Variety of sizes available

Cons:

• Higher energy consumption due to standby heat loss
• Limited hot water supply based on tank size

Tankless Water Heaters

Tankless water heaters, also known as on-demand water heaters, heat water directly as it flows through the device. They don’t store hot water, which eliminates standby energy losses associated with storage tanks.

Pros:

• Energy-efficient
• Endless supply of hot water
• Compact size

Cons:

• Higher upfront cost
• May require upgrades to the home’s electrical system or gas line

Heat Pump Water Heaters

Heat pump water heaters use electricity to move heat from the air or ground to heat water, rather than generating heat directly. They can be two to three times more energy-efficient than conventional electric resistance water heaters.

Pros:

• Highly energy-efficient
• Lower operating costs

Cons:

• Higher upfront cost
• Require specific installation conditions (adequate space and air temperature)

Solar Water Heaters

Solar water heaters use the sun’s energy to heat water. They typically include a storage tank and solar collectors. These systems can be a great option in sunny climates and for those looking to reduce their carbon footprint.

Pros:

• Very low operating costs
• Environmentally friendly

Cons:

• High initial investment
• Dependent on climate and sun exposure
• May require a backup system for cloudy days

Comparing Water Heater Fuel Types

The type of fuel your water heater uses significantly impacts its efficiency, operating costs, and environmental impact.

Electric Water Heaters

Electric water heaters are known for their high efficiency and quiet operation. They’re available in both tank and tankless models.

Pros:

• High-efficiency ratings
• No venting required
• Can be installed almost anywhere

Cons:

• Higher operating costs in most areas due to electricity prices
• Slower recovery rate compared to gas models

Gas Water Heaters

Gas water heaters, fueled by natural gas or propane, typically have lower operating costs than electric models in most regions.

Pros:

• Lower operating costs in most areas
• Faster recovery rate
• Can operate during power outages

Cons:

• Require proper venting
• Slightly lower efficiency than electric models
• Potential safety concerns with gas leaks

Oil-Fired Water Heaters

Oil-fired water heaters are less common but can be an option in areas where oil is a primary heating fuel.

Pros:

• Heat water faster than electric or gas units
• Good option where natural gas isn’t available

Cons:

• Higher operating costs due to oil prices
• Require more maintenance
• Less environmentally friendly

Water Heater Performance Features

After determining a heater’s size and efficiency rating, consider these other important factors that increase longevity and reduce operating costs.

Tank Material

The typical tank is “glass” lined steel (actually porcelain enamel). It contains magnesium or aluminum rods suspended in the tank to fight internal corrosion, which is the number-one reason water heaters fail early.

Stainless steel tanks don’t rust (and therefore don’t need anodes), but they’re more expensive than glass-lined tanks. Their higher cost may be worth it in areas where the water is highly corrosive (acidic) or reactive (full of minerals that encrust the tank walls, slowing heat transfer).

Insulation

Whether foam or fiberglass, the insulation surrounding a gas- or oil-fired tank should be R-16 or higher and R-22 or more for electric. Insulation reduces standby losses — heat that escapes while the unit is idle. Wrapping your tank in a fiberglass blanket won’t make up for insufficient insulation built into the tank.

Heat Traps

These built-in devices — either valves or flexible connectors bent into an inverted U—put a stop to “thermosyphoning,” the tendency for hot water to rise up the supply pipe. If your water heater doesn’t have one built-in, a heat trap can be added during installation (or retrofitted to existing heaters).

Making Your Selection

Factor in warranties and the manufacturer’s reputation before making your purchase. There’s no single source to turn to for this information; talking to a few reputable plumbers and plumbing supply stores should help you narrow the choices. Also, when considering the price of installing a water heater, you may be able to take advantage of rebates or incentives offered by local utilities and municipalities to encourage the purchase of energy-efficient models. (Check the Database of State Incentives for state-by-state listings.) Finally, make sure the heater you’ve chosen will fit in the available space and still leave enough room for servicing.

Once you’re ready to buy, your plumber should be able to order the model you want. Or, you may be able to buy directly from a local home center. In either case, professional installation will take about one to three hours; be sure it includes the cost to remove and dispose of the old heater.

Water Heater Installation Considerations

There are two options for water heater installations: DIY and professional.

DIY vs. Professional Installation

While some homeowners may be tempted to install a water heater themselves, professional installation is often the safer and more efficient choice. Professional installers can ensure proper venting, fuel line connections, and compliance with local building codes.

Space Requirements and Accessibility

Consider the physical space where your water heater will be installed. Ensure there’s enough room for the unit and any required clearances for maintenance. For gas and oil heaters, proper ventilation is crucial for safety.

Water Heater Maintenance Tips

Performing the following tasks annually, or hiring a plumber or HVAC professional to do them, can help your water heater last as long as possible.

• Drain the tank until the water runs clear. If there’s lots of sediment, drain the tank twice a year.
• Inspect the pressure-relief valve for corrosion. If rusty, have a plumber replace it right away.
• Check the combustion chamber and flue vent for rust, corrosion, and obstructions on gas or oil-fired unit. On an electric heater, remove and check heating elements, but shut off the power and drain the tank.
• Remove and inspect anode rod (or rods). Replace if 6 inches or rods of the rod’s core wire are exposed.
• Keep water temperature between 120 and 130 degrees. (Check with a thermometer under the tap.) Higher temperatures speed corrosion.

Water Heater FAQs

How much does a water heater cost?

Water heater pricing can start as low as $150 and reach as high as several thousand dollars, with units averaging between $400-600. This wide price range is due to the varying capacities, features, and designs of water heaters. Ultimately, your local water supply and water heating needs should determine how much to spend on a quality unit.

How long do water heaters last?

On average, storage tank heaters last about 8 to 12 years, while tankless water heaters provide 20 years of hot water. However, despite water heater myths about lifespan, how well you maintain your water heater and how often you use it can play a role in its lifespan.

What are some signs of a failing hot water heater?

Here are some common signs that it’s time to repair or replace your water heater:

• Banging noise
• Pipe corrosion
• Discolored water
• Pooling water
• Water temperature drop

Our Methodology

This Old House has empowered homeowners and DIY-ers for more than four decades with top-notch home improvement advice in the form of television programs, print media, and digital content. Our team focuses on creating in-depth product and service review content. To date, we’ve published over 1,600 reviews on products in the home space, including power tools, outdoor equipment, major appliances, kitchen gadgets, electronics, and more that focus on product quality and helpfulness to our readers.

To provide our readers with the best recommendations possible, we rely on several key sources of information to help guide our selection process.

Initial Research: Our research process began by generating a list of water heaters with a significant number of verified buyer reviews and an average customer review rating of 4–5 stars. We looked at positive and negative reviews alike, focusing on information from both satisfied and critical buyers. 

Expert Insights: To complement our in-house expertise, our team looked at reviews and videos from trusted publications and independent testers, spoke with subject matter experts, and drew insights from reader contributions.

Final Product Selection: We then began fine-tuning our list by replacing older models with the latest versions and eliminating any discontinued models. From there, we compared each model’s feature set to create a final shortlist, selecting the best-in-class options for various buyers, budgets, and scenarios.

Once we conclude our research, we craft a comprehensive, user-friendly article of recommended products and additional information to help our readers make the right purchase.

Questions or Comments?

To share feedback or ask a question about this article, send a note to our team at reviews@thisoldhousereviews.com.