10 Best Electric Tankless Water Heaters 2026 in the United States

The Rheem RTEX-24 24kW 240V Electric Tankless Water Heater offers solid performance for households looking for a reliable source of on-demand hot water. One of its strong points is the flow rate, with the capacity to deliver up to 5.9 gallons per minute, which should be sufficient for multiple outlets running simultaneously. The unit's self-modulating power control and adjustable digital temperature display are user-friendly features that allow for precise temperature adjustments and energy savings, contributing to its high energy efficiency rating of 99.8%. This makes it an economical choice in the long run.

Additionally, the unit is compact, with dimensions of 17.63 inches wide and 18.25 inches high, making it easier to install in various spaces. It is designed for wall mounting, which can save floor space in tight utility areas. However, the power requirements are quite high at 24kW and 240V, which means it might require an upgrade to your electrical system if your current setup isn't compatible. This could add to the installation cost and complexity.

The unit also comes with necessary fittings and aerators, which is a plus. In conclusion, the Rheem RTEX-24 is an efficient and high-capacity option suitable for those who need consistent hot water and have the necessary power infrastructure.

The Stiebel Eltron Tankless Heater – Tempra 36 Plus is a reliable choice for on-demand hot water. One of its main strengths is the ability to provide continuous and unlimited hot water, making it ideal for households with high hot water needs. Its sleek design is another advantage, as it saves space and requires no venting, making installation easier, especially in compact areas. The unit operates quietly due to its electronic switch activation, which can be a significant benefit for maintaining a peaceful home environment.

With a power requirement of 27 kW and 208 volts, ensure your home’s electrical system can support this heater, as it demands substantial power. This model also includes a LED display for easy monitoring and control, adding to user convenience. The copper-sheathed heating element housed in a copper cylinder ensures durable performance. The maximum flow rate is 1.5 gallons per minute, which might be limiting for larger households or simultaneous usage in multiple locations. However, the energy efficiency of this model is high, potentially saving on energy costs over time.

The warranty is another strong point, offering 7 years on leakage and 3 years on parts, which reflects confidence in the product's durability. Weighing 19 pounds and with dimensions of 16.63 inches wide by 14.5 inches high, it’s relatively easy to handle and install. This unit is best suited for small to medium-sized households or specific areas needing hot water on demand.

The WINTEMP 36kW Tankless Electric Water Heater is a strong choice for homeowners seeking a reliable source of endless hot water. It can deliver up to 8.7 gallons per minute, which is enough to supply multiple showerheads or faucets simultaneously without running out of hot water. The heater uses smart technology to adjust its power based on how much hot water you need, which helps save energy and keeps the water temperature steady during use. You can control it remotely via WiFi, adding convenience to your daily routine.

Its compact, wall-mounted design saves a lot of space compared to traditional tank water heaters, making it suitable for smaller homes or tight installation spots. However, it requires a significant electrical setup: a 240V system with a maximum current draw of 150 amps and multiple breakers, which may mean additional electrical work and cost if your home’s wiring isn’t ready. The unit is ETL certified and has several safety features like overheat and leakage protection, giving peace of mind.

It can raise water temperature up to 140°F, fitting most residential needs. While the upfront electrical requirements might be challenging for some, this heater serves those wanting consistent, on-demand hot water with energy savings and modern controls in a compact size.