Best Tankless Electric Water Heater

Hot water is turning out to be more of a necessity in the house instead of a convenience. However, hot water storage tanks can take up a lot of space and energy. Plus they can be difficult to maintain – so many things can go wrong!

This is why a lot of homeowners are now getting themselves tankless water heaters. They are not only smaller and more compact but they also come with energy-efficient features. And the best thing about it? They are so low-maintenance that you only need to check up on them once a year – and you do not need to hire a professional to do so!

Electric tankless water heaters are now in demand because they are the most affordable option to modernize your heating systems at home. Some people might think they have a high upfront cost but given its durability and energy efficiency, the an electric water heater pays for itself in months.

Whether you live all by yourself in a small apartment or you live in a busy household with a family of five, you will find an electric tankless water heater that will suit your needs.

But we understand that it is not easy to choose the best electric tankless water heater. There is no one size fits all solution for your heating needs. With all the technology available today, every unit comes with a handful of features. It could be overwhelming to determine which one would suit your needs best.

But do not worry. In this article, we give you a list of the best electric tankless water heaters that we could find in the market. And to help limit your options, we also have a buying guide to give you all the information you need to make a smart choice and end up with a good product.

Electric tankless water heater reviews

Here, we gather 10 of the most promising electric tankless water heater products that we could find in the market today. Check them all out and take your pick!

Ecosmart ECO18

If you are looking for an electric tankless water heater unit that will not make a huge impact on your energy bill, you should place the Ecosmart ECO18 on top of your list. It is not only energy-efficient but as the name suggests, it is environment-friendly!

The Ecosmart ECO18 has an energy efficiency rating of 99.8% so you can be assured that no energy is wasted. Combine this with the self-modulating technology that allows the unit to adjust accordingly to the hot water demand. The two features added together let you reduce your energy bills by as much as 60%. You do not have to worry about making huge adjustments on your monthly power bills!

This may be an eco-friendly unit but it is powerful enough to supply hot water for two showers and two faucets in warm climates and one shower and one faucet in colder climates.

The digital controls are also intuitive so it is very easy to operate. You can set the water temperature range between 80° and 140°F.

This electric tankless water heater is also made out of durable materials. The components are made of stainless steel and copper. In fact, it comes with a lifetime residential warranty. However, the unit has to be installed by a professional. Otherwise, the warranty will be void.


  • Comes with lifetime residential warranty. You can save money on maintenance, repairs, and parts in the future.
  • Energy-efficient unit. You get to save money by consuming less energy every time you use the water heater.


  • Must be installed professionally. Otherwise, you will not be able to avail of the lifetime residential warranty.

Rheem RTEX-18

If you are looking for a unit from an established brand, you should check out the Rheem RTEX-18. Rheem has always been on the list of high-quality heaters over the years and every unit lives up to the brand’s reputation. The Rheem RTEX-18 is considered to be one of their best products.

The Rheem RTEX-18 uses dual copper immersion heating elements. With such durable and high-quality materials, you can be assured that this is a unit that can last for a long time. In fact, it comes with five-year warranty coverage for the heating chamber and one-year warranty coverage for parts.

This electric tankless water heater uses advanced self-modulation technology that allows it to adjust automatically according to the hot water demand of the household. For instance, when the demand is high, more power is used. But when the demand is low, it uses less power.

The automated system helps lower the electric consumption of the water heater up to 50%. When it comes to energy efficiency, this product is a clear winner.

You still have to measure how much power you really need in your home though because like all units, the Rheem RTEX-18 will also struggle if you push it beyond its capacity.

Because this is a reliable and high-quality unit, it does not come cheap. However, it gives great value for your money so it is still a wise choice.


  • Made out of high-quality and durable materials. You can expect it to last as long as 20 years.
  • Comes with an external digital thermostat control and LED display, making it easy to use.


  • Does not come cheap but it is worth the higher price tag.

The Stiebel Eltron Tempra Plus 36

If you want a high-end unit that has almost everything you would want in a tankless water heater, the Stiebel Eltron Tempra Plus 36 is a great option. It comes in a sleek innovative design and the unit has a very durable build with a detailed control panel and colorful dial. You can also check the current temperature of the incoming water through the LED display.

You should not let its slim and simple looks fool you because this is a powerful unit. It is highly recommended for large households. The unit can do a temperature rise on the water for two showers simultaneously.

The Stiebel Eltron Tempra Plus 36 is energy-efficient. It uses self-modulating technology wherein the system detects the incoming water’s temperature and it only uses the right amount of power to heat it up to your desired temperature. This way, no energy will be put to waste.

This electric tankless water heater has an advanced water flow control feature for high water demand. This means that when used simultaneously, the water flow is reduced just slightly to ensure that hot water is provided without interruption. So, you can enjoy your hot shower even if someone else is doing another hot shower in the other bathroom!

Stiebel gives this unit a 7-year warranty which says a lot about their confidence in their product. It is definitely one of the best electric tankless water heater units in the market.


  • Silent operation so you do not have to worry about waking up anyone with the noise when you need hot water late at night or early in the morning.
  • Intelligent self-modulating tech to lower its power consumption.


  • Installation can be tricky. It might be better if you hire a professional to do the job.

Eemax EEM24027

If you are looking for an electric tankless water heater that can provide hot water for five fixtures, the Eemax EEM24027 is the unit that you should consider. It can give a temperature rise on your water for four fixtures in hot climates and three fixtures in cold climates. If you live in a place that goes through both, this water heater is a winner.

It is also very efficient as it comes with a self-modulation technology that helps lessen your power consumption. This feature lets the tankless water heater only use the energy required to heat up the incoming water.

The unit is compact, making it easy for you to find a place to set it up. The installation process is easy too.

The manufacturer may not be as well-known compared to others in this list but it is a solid option that is found to be reliable by those who have purchased it already.


  • Easy installation so you can do it all by yourself if you want to save money instead of hiring a professional to do it.
  • Can handle more water fixtures in the house compared to other models.


  • Expensive considering it’s a lesser-known brand

Rheem RTEX 13

If you only have one bathroom in your home but you want a high-quality tankless water heater, you should consider getting the Rheem RTEX 13. The Rheem RTEX 13 is one of the most compact models in the market today. It can easily fit in cramped and tight spaces. You can even fit it above or below the sink. You can install it anywhere no matter how small your place can be.

The unit comes with a digital thermostat and user-friendly controls that make it effortless for you to adjust the settings. The unit comes with nine settings. There is also an LED display to show you the current temperature the water is at.

The Rheem RTEX 13 claims to be 99.8% energy-efficient. You can save a lot of money on your monthly energy bill compared to normal residence tankless heaters.

You should know though that this unit is considered perfect for smaller households because it has a low output rate. The unit can only provide a temperature rise for one shower at a time. The only exception is if you have low-flow fixtures in your home. It is best to be treated as a point-of-use water heater for your home.


  • Digital thermostat and controls for easy usage.
  • Compact built. It is small enough for you to install anywhere you want.


  • Low output rate. This is why it is best for one-bathroom homes and tiny apartments.

Bosch Thermotechnology WH27

If you are looking for an upscale tankless water heater that can provide premium performance, the Bosch Thermotechnology WH27 is a unit that should be on top of your list.

This unit guarantees 97% thermal efficiency, making it one of the most superior tankless heaters on the market. It is efficient enough to knock off two-thirds of your monthly energy bill. It operates quietly too!

The Bosch Thermotechnology WH27 has a capacity of 26.9 kW. It can heat water for three fixtures simultaneously. You can expect consistent temperature from the unit even when all fixtures are being used since the heating elements are encased in polymer. The water heater also has a built-in activation flow sensor that stabilizes the temperature.

It weighs less than 20 pounds so you can easily have it mounted on the wall. Installation is a breeze and you can have it up and running in less than an hour.

The Bosch Thermotechnology WH27 may be on the expensive side as it is an upscale unit but it has proven to be worth every penny.


  • Quiet operation. This unit can operate silently so you can take hot showers late at night if you want to.
  • 97% thermal efficiency. You get your hot water while consuming less energy.


  • This unit is expensive compared to other models.

Sio Green IR260 POU

If you are looking for something unique and high tech, you should check the Sio Green IR260 POU. This is a high-tech infrared electric tankless water heater, making it stand out in the market.

This unit makes use of innovative technology that features a no-coil and no-metal design. This means that you do not have to worry about corrosion and rust with this water heater.

The best part about it is that it is an affordable model. This makes the Sio Green IR260 POU a great choice if you are looking for a water heater that is light on the pocket too.

But despite its high tech features, the Sio Green IR260 POU has a low flow rate at 1.5 GPM. This drastically limits the hot water supply you can get from it. Because of this, we recommend that you use this model as a point-of-use water heater instead of treating it as a whole house tankless water heater.


  • Infrared heating eliminates the need for quartz-based heating elements. This makes it a low-risk unit.
  • This tankless heater has innovative technology making it stand out from the rest of the products available in the market today.


  • Has a low flow rate so it is best as a point of use water heater.

Titan SCR2 N-120

If you want an affordable tankless water heater that can give you an abundant hot water supply, the Titan SCR2 N-120 is a great pick.

Titan is known to be one of the best water heater manufacturers in the industry and they collaborated with Niagara Industries to create this affordable yet powerful unit.

The Titan SCR2 N-120 is very lightweight – it only weighs 8 pounds. You can easily install it on any wall or surface. The unit has a tan steel finishing that makes it blend with any theme of the room.

Although the unit is very light and compact, it is powerful enough to give you a flow rate of 4.0 gallons per minute. It also has an energy efficiency rating of 99.5%.


  • This tankless heater comes with an affordable price tag compared to other brands.
  • Lightweight enough to be installed at any kind of wall with no worries.


  • The starting water temperature is actually high (105°F). This may be too much for some people.

Marey Power Pak Plus

If you are looking for a good electric tankless water heater that is a great budget pick, the Marey Power Pak Plus is an inexpensive unit that will serve you well if you live in an area with a warm climate.

The unit is very easy to install and it is simple – you do not have to deal with extra temperature control settings that you do not really need. It is all very basic, giving you a completely uncomplicated experience.

The Marey Power Pak Plus tankless water heater is not only affordable but it also helps you save money because it is a highly efficient unit. It can save up to 60% on your power bills.

You should know that this unit is best for tropical climates or where the weather is mostly warm. Under these conditions, it can give a temperature rise for two fixtures simultaneously – such as one shower or one faucet, or two showers. But if you live in a colder climate, you should be warned that this tankless water heater will only work well for one fixture at a time. Try using more than one and the unit will struggle. If this is your case, it is best if you use it as a point-of-use heater instead of a whole house electric tankless heater.


  • This is an affordable tankless heater that will fit most budgets.
  • This tankless heater is very basic and simple, making it very easy to use.


  • Not the ideal house electric tankless water heater for areas with cold climates as it will not be able to provide a stable hot water temperature.

Ecosmart ECO MINI 2.5

If you are simply looking for a point-of-use water heater or an additional one for the fixtures that your already existing water heater could not accommodate, you can get your hands on a mini electric tankless water heater like the Ecosmart ECO MINI 2.5. This is a great choice for those who just need an additional unit or for those who only want a heater for one shower or one faucet.

The Ecosmart ECO MINI 2.5 can supply hot water for 2 faucets that run at the same time, although you have to wait for about 3 minutes before the hot water starts to flow.

It is actually considered to be one of the best under-sink tankless heaters out in the market today. All you have to do is tap into the water line and install it directly under the sink! No need to resize your home’s heating system just to accommodate another fixture!

This unit has a compact and sleek design. It also comes with a temperature display to let you easily see what temperature the hot water output is in.


  • Easy installation. You can do the work yourself if you do DIY installations.
  • Small and compact. You will not have a hard time looking for a place to install it.


  • Can’t handle high demand for hot water. This unit is best for homes with low demand for hot water.

Electric tankless water heater – buying guide

Buying an electric tankless water heater is an investment that you would want to last for a long time. Because of this, you have to choose your unit well. Here is a list of the things that you should consider when picking out the best electric tankless water heater for your hot water needs.

Water flow

Tankless water heaters heat the water on demand but they also have their limits when it comes to the volume of water that flows through the system. If the demand exceeds that capacity, the temperature will be compromised.

Because of this, you have to think about your hot water needs first. Think about how many fixtures you want to run at the same time (two showers and one faucet, one shower, and one kitchen faucet). Once you identify how much hot water is needed in your home, you have a good idea how much hot water flow is needed.

Groundwater temperature

Ever wonder why the climate matters in the reviews above? This is because the groundwater temperature also matters in how much power an electric tankless water heater needs.

Colder climates have colder groundwater temperatures. This means the tankless water heater will have to exert more power to heat the water. Warmer climates already have warm or room-temperature groundwater so tankless water heaters in this climate do not need to exert a lot of power to produce hot water.

Energy efficiency

Since we are talking about electric tankless water heaters, the unit will definitely impact your electric bill. You have to choose a unit that is efficient enough to reduce its power consumption so that they do not use up a lot of energy.

Choose a product with a high energy efficiency rating so that you will not experience a major increase in your power bill. Look out for features like self-modulation which helps reduce energy consumption when the hot water demand is low.


A tankless water heater should be easy to control. This is important also if you have kids or seniors in your home who would want a hot shower. The water temperature control should allow you to adjust the heat and should be easy to understand and use.

You should also consider getting a unit with a thermostat that lets you adjust the incoming water temperature easily so you do not have to worry about the water coming in too hot.

Electrical demands

Of course, since this is an electric unit, you have to make sure that your home can meet the electrical demands of your tankless water heater. Most units need 120 to 160 amps to power up their heating coils.

If you are unsure, you can hire a professional electrician to check and do the upgrade of your electrical system if needed to accommodate your water heater.


Is the unit easy to install? Most electric tankless water heaters are easy to install and you can even save money by doing the job yourself. This is great if you are handy with your tools.

But before you do this, make sure you check the warranty conditions first. Some units only give warranty coverage for units that have been installed professionally. Otherwise, the warranty will be void.


When it comes to tankless water heater productss, most manufacturers provide similar warranty terms although some would stand out by giving lifetime warranties.

As mentioned before, some warranties will be considered void if you try to install the unit by yourself so make sure to read the conditions properly before committing to a product.

Reputation and reviews

Lastly, you should look into the manufacturer’s reputation and read up on tankless water heater reviews.

Do not simply rely on the brochure-like product introductions that online shops and their websites supply. Sometimes, you can read a product description that is too good to be true but find a lot of raving customers on customer reviews or feedback. So make sure you do your research and read everything.

Also, make sure that the manufacturer has a good reputation and standing in the industry. Established brands already have a reputation to protect so they make their best to be consistent in producing units that can live up to their name.

If you are dealing with an unknown or unfamiliar manufacturer, make sure to read customer reviews to ensure that you are dealing with a good product.


What is the best electric tankless water heater on the market?

The best water heater is one that ensures you get a steady hot water supply while using up a minimal amount of electricity.

According to our review, we vouch for the Ecosmart ECO 18 unit. It comes with a 99.8% energy efficiency rating, making it the most efficient tankless electric water heater in our product review list. Aside from being energy-efficient, it has the self-modulation technology that makes the unit use only the necessary amount of power to heat up the incoming water. So, if you live in a warm climate, you do not consume so much electricity since the unit will not need a lot of power to heat up your water.

The Ecosmart ECO 18 water heater is also powerful. If you are in an area with a warm climate, can provide a steady supply of hot water for two showers and two faucets. If you are in an area with a cold climate, it can provide a steady supply of hot water for one shower and one faucet. It can accommodate more fixtures compared to most models on the list. This makes it a great water heater choice for areas that go through both warm and cold climates!

Overall, the Ecosmart ECO 18 electric water heater is energy efficient yet powerful enough to cater to your hot water needs. You can have unlimited hot water any time you want!

What size tankless electric water heater do I need?

A tankless water heater’s size is calculated by how many and what type of fixtures will it serve. The result is the flow rate, measured by gallons per minute (GPM).

So, the first step is to identify what fixtures you want to have hot water that could possibly run simultaneously. It could be a shower, your kitchen faucet, and your bathroom faucet or two showers and the kitchen faucet. Add the GPM for each fixture and the result is how much GPM your tankless water heater should handle.

Generally, a bathroom and kitchen faucet has a flow rate of 0.5 GPM. A shower has a flow rate of 2.5 GPM. A dishwasher has a flow rate of 1.0 GPM. And a washing machine has a flow rate of 1.5 GPM. Take note that these are general estimates.

Figure out which fixture will demand hot water in your house and add up the GPM.

What is the difference between point of use (POU) and whole house systems?

As the name suggests, a whole house tankless system is a water heater that handles all the hot water fixtures in your house. Because of this, you should install it in a central location and it should have enough power to provide hot water on demand. Generally, you end up with less hot water with an entire home system water heater since the hot water has to travel a longer distance to reach some of the fixtures. The heat could also be compromised when three or more fixtures are being used at the same time unless you are using a premium unit.

POU systems are installed closer to the plumbing fixture and usually serves just one fixture, although there are some models that can handle two. These units are smaller in size and are often installed underneath the sink or by the shower. POU units are more efficient in delivering hot water since the water travels a shorter distance. They are often a choice for those that only needs an additional water heating unit for some fixtures that the existing water heating system could not accommodate or for those who only need hot water for one fixture in the house such as the shower.

What is the downside of a tankless water heater?

The main downside of a tankless water heater is that it has a higher upfront cost compared to water heaters that come with a tank. The unit and the installation can cost twice as much as a tank water heater.

An electric tankless water heater also has a limited capacity when it comes to providing hot water. If you have several bathrooms and sinks in your home and they are all being used, your electric water heater will struggle to accommodate everything and would lead to unstable temperatures.

Another downside of an electric tankless water heater is that it will not be able to give you hot water if you have a power outage. Tank-style water has preheated water in stock so you can still take advantage of it even when the power is out.

Like all things, even the best tankless water heaters have their pros and cons. But the real question is if the benefits outweigh the setbacks. When it comes to electric tankless water heaters, we believe that they are still worth having in your home.

Do tankless electric water heaters ever work on cold climates?

The need to demand hot water is great in areas with cold climates. When it comes to hot water on demand like tankless water heaters, people tend to use a gas tankless water heater because they have more power compared to electric-powered units. However, this does not necessarily mean that electric tankless water heaters do not work in cold climates.

Most electric tankless water heaters are just not powerful enough to accommodate multiple fixtures in a cold climate but there are premium models that can handle colder water temperatures without struggling. However, these high-end units can be expensive.

How you install it also matters. Outdoor electric tankless water heaters are not as reliable as indoor electric tankless water heaters during winter. A gas tankless water heater is more durable in outdoor settings.

If you want to use an electric tankless water heater for colder climates, make sure that it comes with freezing protection. Also, you have to install it somewhere warm and dry – preferably indoors (even if it says it can be installed outdoors).

Are electric tankless water heaters worth it?

Electric tankless water heaters are definitely worth it because unlike water heaters that come with a tank, tankless water heaters can give you heat water on-demand. This means it only uses up energy when you need it. When you have a tank water heater, the water heater runs all the time – consuming a lot of power and increasing your energy bill.

Tankless electric water heaters are so much cheaper compared to a gas tankless water heater. Because the process does not involve combustion, they are more reliable in the long run. Also, you do not have to deal with additional setups for ventilation and gas pipes or worry about leaks.

The best tankless water heaters may be more expensive compared to tank-style water heaters but they also last twice as long. The upfront cost may be discouraging for some homeowners but in the long run, it actually helps you save more money through its energy-efficient features and durable design.

Electric water heaters are also incredibly low maintenance. You do not have to hire technicians all the time to make sure that your heating system is running well. This makes the maintenance cost cheaper compared to the maintenance cost of a gas tankless water heater.

The best thing about tankless water heaters is that they are great space savers. You no longer need to make room for a bulky tank. Most models come in compact sizes and designs and are very lightweight that you can easily mount them on the wall with no worries or difficulties.

If you choose an electric tankless water heater, you are also doing Mother Earth a favor. Unlike a gas tankless water heater, an electric-powered tankless water heater is greenhouse emission-free – no need to worry about your carbon imprint!


Remember, your water heater is an important part of your home. A tankless water heater is a huge and important purchase. There are so many fixtures that demand hot water and would make your life easier. You must do your research and checks all your available options before you settle on a final decision to end up with the best tankless water heater.

With this product review and buying guide, you now have enough information to identify which tankless water heater would work best for your water heating needs. After going through the list of considerations, all your choices will be filtered and now all you have to do is purchase the best pick out of the list and install it in your home. Now you can enjoy having hot water whenever you need it!

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