10 Best Electric Tankless Water Heaters 2025 in the United States

The Stiebel Eltron Tempra 24 Plus is a solid choice for those seeking a reliable electric tankless water heater. One of its standout features is the continuous flow technology, which ensures that you won't run out of hot water during a shower. This system intelligently adjusts water flow to maintain a consistent temperature, making it great for households with higher hot water demands. Its sleek, compact design is also a plus, saving you space while providing on-demand hot water without the need for venting.

Energy efficiency is another strong aspect, as this unit utilizes auto-modulation to conserve energy, which can lead to lower utility bills. The digital temperature display and preset settings offer easy control, making it user-friendly, even for those who aren’t technically inclined. Plus, the generous warranty—7 years for leakage and 3 years for parts—adds peace of mind regarding its reliability.

There are some considerations to keep in mind. The Tempra 24 Plus requires a substantial electrical service of 150 A, which may necessitate upgrades in some homes, potentially adding to installation costs. Additionally, while it can provide ample hot water for most situations, it may struggle with simultaneous high-demand usage, as it reduces flow when demand exceeds capacity. This could be a drawback in larger families or homes where multiple showers and appliances may be in use at the same time.

The EcoSmart ECO 11 Electric Tankless Water Heater offers a compact and efficient solution for providing hot water on demand. With a flow rate ranging from 1.3 to 3.1 gallons per minute, it is well-suited for small applications like a bathroom or office breakroom. The patented self-modulating technology ensures that water temperature remains consistent within 1 degree of the selected setting, providing reliable and endless hot water when needed.

This model is highly energy-efficient, boasting 99% thermal energy efficiency, meaning it only heats water when in use, which can lead to significant energy savings compared to traditional tank heaters that continuously maintain water temperature. Measuring just 11.5 x 8 x 3.75 inches and weighing 6.5 pounds, it's 90% smaller than traditional water heaters, making it easy to install on a wall or at the point of use. However, it draws a significant amount of power at 13KW and requires a 240-volt electrical connection with a 54-amp draw, which may necessitate electrical upgrades for some homes.

The product comes with a lifetime warranty covering electronics, the exchanger, and the heating element, but this warranty only includes the cost of the heater itself and excludes labor and incidental damages, which could be a drawback for some users. This unit is ideal for those looking for a space-saving, energy-efficient solution for low-flow hot water needs.

The Rheem 18kW 240V Tankless Electric Water Heater is a solid choice for those looking for an efficient and reliable source of hot water. With a maximum flow rate of up to 4.4 gallons per minute (GPM), it can meet the demands of small to medium households effectively. One of its standout features is the external digital thermostatic control with a precise +/- 1 degree accuracy, allowing users to easily set and maintain their desired water temperature.

Energy efficiency is another strong point, boasting an impressive 99.8% efficiency rating, which can help reduce electricity bills over time. The self-modulation technology adjusts power based on hot water demand, ensuring energy is used only when needed. Additionally, it is compact in size, making it suitable for installations in tighter spaces.

Installation is made easy with the bottom 3/4 inch NPT water connections and threaded fittings, which simplify the process for homeowners and professionals alike. However, it’s important to note that this model is designed for wall mounting, which may require additional considerations for some users. Some users may find that the 18kW power rating is not sufficient for larger households with multiple simultaneous hot water needs. While it serves well for typical use, those with higher demand might need to consider a more powerful unit. Additionally, it may require professional installation, which can add to the overall cost.