The 10 Best Water Heaters of 2021

Get the right temperature at home with the right fit for your household

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Our Top Picks
The Power Vent of this model propels exhaust up to 100 feet horizontally or vertically and improves energy efficiency.
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This electric model has a self-cleaning dip tube to reduce sediment and extend tank life.
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Best Tankless, Electric:
Ecosmart ECO 27 at Amazon
Even in cold weather climates with incoming water at 37 degrees F, the ECO 27 can supply hot water at a flow of 2.7 GPM.
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With 180,000 BTU, this tankless water heater puts out hot water at a rate of 7.5 GPM, enough to supply 3 fixtures at once.
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This unit comes with a six year warranty and features an anode rod to slow corrosion from hard minerals.
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Delivering 65 gallons of hot water in the first hour of use, this model is affordable but capable for 3 to 4 person homes.
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Save space but get plenty of hot water from this compact model with a first-hour delivery of 66 gallons.
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Install this mini-tank water heater under any sink to boost hot water output where you need it most in your home.
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Suitable for warm climates, a water heater with a heat pump is an energy-efficient pick for an electric water heater.
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Using water pressure as low as 20PSI, this tankless heater can heat water to temperatures ranging from 50 to 140 degrees.
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A water heater is an essential part of your home’s plumbing system. Usually tucked away in a closet or the basement, it’s easy to take it for granted—until you’re the last person to take a shower and wind up with cold water. By choosing the right size water heater for your home, you can avoid this chilling experience and have plenty of hot water for showers, handwashing, kitchen tasks, appliances, and more. 

Gas or electricity powers the heating function of water heaters. Tank-style heaters are the most common for residential use, but tankless water heaters are great for their unlimited hot water supply and space-saving design.

Whether your home is configured for a gas or electric water heater, these are the top models to consider on the market now.

Best Overall, Gas: Rheem Performance Power Vent Natural Gas Tank Water Heater

Rheem Performance Power Vent Natural Gas Tank Water Heater

Heating Source: Gas | Type: Tank | Tank Size: 40 gallons | Heating Power: 36,000 BTU per hour | Flow Rate: Not applicable

What We Like
  • Vents horizontally or vertically up to 100 feet

  • Draws air from the outside

    Easy to relocate

  • Energy Star qualified

What We Don't Like
  • Only a one year warranty on in-home labor

Natural gas water heaters provide an energy-efficient way to ensure that you have a supply of hot water ready for household use. The Rheem Performance Power Vent series is a popular pick for a tank-style gas water heater and is available in tank capacities ranging from 40 to 75 gallons. 

Equipped with a fan-propelled exhaust system, the advantage of this gas water heater is its ability to vent to the outside either horizontally or vertically—up to 100 feet. This expands installation possibilities and means that you can more easily relocate your gas water heater. In addition, the water heater draws air in from the outside, rather than using ambient air for system functions. Energy efficiency is improved, and this model carries a uniform energy factor rating of 0.69—making it Energy Star qualified.

Like many other gas water heaters, the tank of this model is lined with glass while an anode rod provides protection against corrosion from hard minerals present in your water supply. A 6-year limited warranty applies to the tank and parts, but take note that there is only a 1-year warranty on in-home labor. 

Best Overall, Electric: Rheem Performance Plus 50 Gallon Electric Tank Water Heater

Rheem Performance Plus 50 Gallon Electric Tank Water Heater

Heating Source: Electric | Type: Tank | Tank Size: 50 gallons | Heating Power: 5,500 watts | Flow Rate: Not applicable

What We Like
  • Dual-element design

  • Lower element is made of stainless steel for durability

  • LED monitor

The Rheem Performance Plus series offers a combination of features and benefits that homeowners will appreciate in an electric water heater. The 50-gallon tank offers plenty of capacity for households of 3 to 5 people and delivers 62 gallons of hot water in the first hour. Like most other electric water heaters, this model features a dual-element design. Both elements are 5,500 watts, but the hardworking lower element is made of stainless steel for increased durability and resistance to corrosion. The upper element is made of copper. 

Rheem’s Performance Plus water heaters also include an LED monitor, which makes it much easier to set your target water temperature and monitor element functions. The manufacturer’s limited warranty extends for 9 years on parts, and the in-home labor warranty is valid for 2 years. 

Best Tankless, Electric: Ecosmart ECO 27 Electric Tankless Water Heater

EcoSmart ECO 27 Electric Tankless Water Heater

Heating Source: Electric | Type: Tankless | Tank Size: Not applicable | Heating Power: 27 kilowatts | Flow Rate: Between 2.7 and 6.5 gallons-per-minute

What We Like
  • Compact size

  • Lightweight

  • Can adjust the temperature in 1-degree increments

What We Don't Like
  • Some reports of leaking

EcoSmart is a popular name for tankless electric water heaters and the ECO 27 is well-equipped to handle hot water needs for your home. This larger model offers flow rates between 2.7 and 6.5 GPM, depending on incoming water temperatures. To put this in perspective, it’s usually sufficient to operate a shower and sink fixture simultaneously, but homes in warmer regions can receive flow from multiple showers and sinks at once. 

A digital control panel allows you to adjust the temperature in 1-degree increments from 80 to 140 degrees Fahrenheit. This makes it possible to adjust the water temperature to your precise needs. Measuring 17 x 17 inches, this smaller unit mounts on the wall in your basement or utility closet—leaving more floor space for cleaning supplies or other storage needs. Efficiency and space savings are two big reasons to choose a tankless water heater.

Best Tankless, Gas: Rinnai RL Series HE+ Tankless Hot Water Heater

Rinnai RL Series HE+ Tankless Hot Water Heater

Heating Source: Gas | Type: Tankless | Tank Size: Not applicable | Heating Power: 180,000 BTU | Flow Rate: 7.5 gallons per minute

What We Like
  • Compact size

  • ThermaCirc360 technology

What We Don't Like
  • Ultra low NOx burner

For a highly efficient and compact water heater, consider the Rinnai RL75iN Natural Gas Tankless Water Heater. This model carries a uniform energy rating of 0.81 and supplies up to 7.5 GPM of hot water for showering, hand washing, or any other household need. You’ll also be able to reclaim space in your utility closet or basement since this tankless water heater measures just 23 x 14 inches. 

A unique feature of this tankless gas water heater is ThermaCirc360 technology. This feature helps to improve hot water delivery rates by recirculating hot water through your pipes. Despite powerful heating capacity, it’s worth noting that this water heater has an ultra-low NOx burner.  

Best Budget, Electric: Rheem Performance Electric Tank Water Heater

Rheem Performance Electric Tank Water Heater

Heating Source: Electric | Type: Tank | Tank Size: 40 gallons | Heating Power: Two 4500-Watt elements | Flow Rate: Not applicable

What We Like
  • Affordable

  • 6-year warranty

  • Anode rod to slow corrosion

What We Don't Like
  • May need to replace the copper elements over time

Balance budget with functionality when you pick an electric water heater like this model from Rheem. The Performance series carries a 6-year warranty and is available in 30, 40, and 50-gallon tank sizes. Regardless of which size you choose, the tank is lined with glass and features an anode rod to slow corrosion from hard minerals. 

With the first-hour delivery of 53 gallons of hot water, the 40-gallon tank model is sized right for households of 2 to 4 people. It’s a popular pick for a budget electric water heater and includes a pair of 4,500-watt copper heating elements. While mid-range water heaters typically include at least one unit of stainless steel (usually the lower element), opting for a water heater with copper elements means more money saved upfront—but the potential for a shorter life of service from the heating elements. However, these screw-in elements can be replaced if the need arises in the future. 

Best Budget, Gas: A. O. Smith Signature 40-Gallon Tall 6-Year Limited 35500-BTU Natural Gas Water Heater

A. O. Smith Signature 40-Gallon Tall 6-Year Limited 35500-BTU Natural Gas Water Heater

Heating Source: Gas | Type: Tank | Tank Size: 40 gallons | Heating Power: 35,500 BTU | Flow Rate: Not applicable

What We Like
  • Simple

  • Affordable

  • Anode rod to protect against corrosion

  • Self-cleaning dip tube

What We Don't Like
  • Doesn’t meet the requirements for an ultra low NOx water heater

  • Might not work for larger households or multiple bathrooms

For homes already equipped with a gas water heater, it’s generally in the best interest of your budget to stick with a water heater powered by natural gas. The simple but efficient 40-gallon gas water heater from the A. O. Smith Signature series is an affordable choice. It’s equipped with a 35,500 BTU low NOx burner, but take note that it doesn’t meet the requirements for an ultra-low NOx water heater, as required by some states.  

The features and specifications of this water heater are frills-free but meet the needs of most households. The interior of the water tank features a ceramic coating, while an anode rod provides additional protection against corrosion from hard minerals present in your water supply. This model also has a self-cleaning dip tube, which is not always seen on budget gas water heaters. The manufacturer backs the Signature series up with a 6-year limited warranty. 

Suitable for most 3 to 4 person households, the 40-gallon tank water heater supplies 65 gallons of hot water in the first hour and has a recovery rate of 38 gallons per hour, assuming that you need to raise the temperature of the water by 90 degrees Fahrenheit. For larger households or multiple bathrooms, you might consider upgrading to a model with a 50-gallon tank capacity. 

Best Short: A. O. Smith Signature Premier 50-Gallon Short 12-Year Limited 5500-Watt Double Element Electric Water Heater

A. O. Smith Signature Premier 50-Gallon Short 12-Year Limited 5500-Watt Double Element Electric Water Heater

Heating Source: Gas | Type: Tank | Tank Size: 50 gallons | Heating Power: Two 5,500 watt stainless steel elements | Flow Rate: Not applicable

What We Like
  • Compact

  • Digital control panel

  • Energy Smart® mode

  • Self-cleaning dip tube

What We Don't Like
  • Some might find the features too complicated

Save space without shortchanging your hot water supply when you choose this 50-Gallon short electric water heater from A. O. Smith. The tank fits in compact closets, under stairs, or in attics, measuring 49.25 inches tall and 23 inches in diameter. It’s equipped with two 5,500 watt stainless steel elements and can handle the hot water needs of households with 3 to 4 people. 

Part of the Signature Premier series, this short water heater carries additional features that homeowners will find helpful. For example, it features a digital control panel that makes it simple to see the water heater’s current temperature settings or make adjustments to the target temperature. It also has an Energy Smart® mode that can learn your hot water usage patterns and reduces the energy spent on heating water during periods of minimal use. In addition to these energy-saving features, this water heater is also designed with durability in mind. It has a self-cleaning dip tube to reduce the build-up of sediment in your water tank. The tank and components are backed by a 12-year limited warranty.

Best Point of Use: Bosch Electric Mini-Tank Water Heater Tronic 3000 T

Bosch Electric Mini-Tank Water Heater Tronic 3000 T

Heating Source: Gas | Type: Mini-tank | Tank Size: 4 gallons | Heating Power: Not applicable | Flow Rate: Not applicable

What We Like
  • Compact

  • Lightweight

  • Boosts the supply of hot water

What We Don't Like
  • Anode may need replacing over time

Boost your supply of hot water where you need it most by installing a point-of-use water heater. The Bosch Tronic 3000T is a mini-tank water heater that fits under kitchen or bathroom sinks. This model features a 4-gallon tank and is equipped to keep two sinks supplied with hot water. 

Like most point-of-use water heaters, the Bosch Tronic 3000T plugs into a standard 120V outlet. Adjust the temperature of your water supply from 65 to 145 degrees Fahrenheit. While not designed for whole house water heating, installing a mini-tank water heater is a simple way to boost the supply of hot water to a sink located far from your primary water heater. 

Best Hybrid: A. O. Smith Signature Premier 50 Gallon Electric Water Heater with Hybrid Heat Pump

A. O. Smith Signature Premier 50 Gallon Electric Water Heater with Hybrid Heat Pump

Heating Source: Electric | Type: Hybrid | Tank Size: 50 gallons | Heating Power: Two 4,500 watt copper heating elements | Flow Rate: Not applicable

What We Like
  • Hybrid heat pump

  • Energy Star certified

What We Don't Like
  • Expensive

Boost the energy efficiency of an electric water heater by opting for a hybrid model, like this version from A. O. Smith. The Signature Premier Electric Water Heater is equipped with a hybrid heat pump, which uses ambient air to warm water on demand. While electric water heaters are generally not known for being energy efficient, this model is Energy Star certified. It can supply hot water to households of 3 to 4 people and has a first-hour delivery of 46 gallons. 

At the same time, this model is equipped with two 4,500 watt copper heating elements. During periods of high demand for hot water, these electric elements can ensure that you have enough hot water for showers, laundry, washing dishes, and more. 

Best Portable: Eccotemp L5 1.5 GPM Portable Outdoor Tankless Water Heater

Eccotemp L5 1.5 GPM Portable Outdoor Tankless Water Heater

Heating Source: Connects to a propane tank | Type: Tankless | Tank Size: Not applicable | Heating Power: Not listed | Flow Rate: 1.5 gallons per minute

What We Like
  • Great for outdoor use

  • Compact

  • Portable

What We Don't Like
  • Need to supply your own hoses or piping

Make sure that you have hot water on demand, even in the great outdoors with this portable water heater from Eccotemp. The L5 is a compact unit that is popular for camping, off-grid living, or providing warm water in the backyard and delivers a flow rate of up to 1.5 GPM. 

The portable water heater connects to a 20-pound propane tank and two D batteries—which power the electronic ignition. You’ll need to supply the hoses or piping to connect the heater to your water source. Keep in mind that if you’re drawing water from a non-pressurized source, like a rain barrel, lake, or tank, you’ll need to also purchase a 12V pump. 

Final Verdict

The Rheem Performance Power Vent Gas Water Heater (view at Home Depot) offers the most flexible placement options of a tank-style water heater. This model can be vented outside a distance of up to 100 feet, which could help you reconfigure your utility closet and reclaim some square footage in your home. However, you'll pay more for this model with a fan-equipped exhaust system. For a budget-friendly option and a home set-up for an electric water heater, you can save a bundle with the simple but functional Rheem Performance Electric Water Heater (view at Home Depot). The 40-gallon tank model delivers 53 gallons of hot water in its first hour of use.

What to Look for in a Water Heater

Gas or Electric

The choice between an electric and gas-powered water heater depends on a number of factors, including local utilities and your own personal preference. Electric water heaters are favored by people looking for low upfront costs and households that aren't set up with natural gas. While gas heaters are more expensive upfront, they can save you hundreds of dollars a year, depending on energy costs in your area.

Tankless or Tank

Tank water heaters keep a certain amount of hot water in a tank at any given time, ready to send to multiple appliances at once. Tankless water heaters quickly heat incoming water as you need it, and take up less space than a water heater with a tank. However, one unit may not be able to provide hot water to multiple fixtures at once, so you may need to buy multiple water heaters for your home.

Tank Capacity

If you go the tank route, make sure that your water heater can store enough water hot to keep up with your family. While tank water heaters can provide water for multiple places at once, it will take longer to heat up new water than a tankless heater, which could leave you with an unexpected cold shower.

FAQ
  • How do water heaters work?

    Tank-style water heaters use a dip tube with an outlet at the bottom of the tank to fill the water heater with cold water. An internal thermostat monitors the temperature of the water inside the tank and activates a heating element or burner to warm the water to a pre-set temperature.

    In electric water heaters, dual heating elements work to warm the water. Usually, the bottom element works harder to heat the incoming cold water while the top element only kicks on if the heated water in the top half of the tank becomes depleted. 

    For gas water heaters, a pilot light or electronic ignition system ignites gas flowing to a burner. The burner heats the water within the tank to a target temperature before shutting off. This process produces exhaust, which must be vented to the outside of the home.

    Tankless water heaters don’t store water. Instead, they use either gas or electric heating elements to warm water as it passes through the unit. The flow rate of hot water will depend on how cold the incoming water temperature is, but most units can supply between 2 to 7 GPM. 

  • How do you drain a water heater?

    Draining a water heater should be done regularly (every 6 to 12 months) to prevent a build-up of sediment in the bottom of the tank. To drain the tank, you’ll want to have a drain hose on hand and be prepared with a drain cap or new drain valve, in the event that the valve won’t close properly at the end of the process.

    To drain a water heater, first, flush the system with full water pressure. Connect the drain hose and open the drain valve briefly before shutting it again. Any sediment lodged in the valve will be dislodged, helping the system to drain more quickly.

    Next, shut off your water heater by disconnecting it from the gas or electric power supply. Turn off the water supply, as well. Then, with the drain hose still connected from your quick flush, open the drain valve. You won’t see much water flowing out until you allow air into the tank. To do so, you’ll have to disconnect the hot water pipe at the top of your water heater and move it to the side. The tank will begin draining.

    Once your water heater tank is drained, you should flush it with fresh water. Leave the hot water pipe disconnected for this step. To flush the tank, turn the water supply on for a few moments before shutting it off again. Doing so will put several gallons of water through the tank at a time. 

    Finally, disconnect your drain hose and close the drain valve. Reconnect the hot water pipe at the top of the tank. Turn the water supply back on. To remove any air in the lines and test the system, turn on the hot side of a plumbing fixture (like your kitchen sink or tub) and let it run until it produces a steady stream of water. Double-check that the drain valve is not leaking. Finally, relight the pilot light for gas tank heaters or plug in your electric water heater to resume normal operation.

  • How long does a water heater last?

    Water heaters have varying service life expectations, but many units can be expected to last between 8 and 12 years. In some cases, you may even get 20 years of use from a water heater. The quality of your water supply can have a big impact on how long a water heater lasts since heavy minerals and sediment in the water can lead to corrosion over time. 

    The manufacturer’s warranty periods vary depending on the model you choose. Common warranty periods are usually 6, 9, or 12 years. 

Why Trust the Spruce?

This article was researched and written by Erica Puisis, who is a professional writer that specializes in large and small home appliances, along with home improvement features and plumbing fixtures. Erica has been writing for The Spruce since 2017 and has covered everything from home saunas and infrared heaters to water softeners. To choose the best options for this article, she consulted dozens of customer and third-party reviews, considering each product's heating source, heating power, and tank size. She also evaluated each model's portability and durability before making her final selections.

Article Sources
The Spruce uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. "Storage Water Heaters". Energy.Gov, https://www.energy.gov/energysaver/water-heating/storage-water-heaters.

  2. "Efficient Natural Gas". American Gas Association, 2021, https://www.aga.org/natural-gas/efficient/.

  3. "Water Heater Key Product Criteria". Energy Star, https://www.energystar.gov/products/water_heaters/residential_water_heaters_key_product_criteria.

  4. Delforge, Pierre et al. "Very Cool: Heat Pump Water Heaters Save Energy And Money". NRDC, 2016, https://www.nrdc.org/experts/pierre-delforge/very-cool-heat-pump-water-heaters-save-energy-and-money.

  5. "Natural Gas Water Heaters". American Gas Association, 2021, https://www.aga.org/natural-gas/in-your-home/water-heaters/.

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