10 Best Tankless Hot Water Heaters 2026 in the United States

The Rheem RTEX-24 Electric Tankless Water Heater is a solid choice for those seeking an efficient and high-capacity water heating solution. One of its major strengths is its impressive flow rate of up to 5.9 gallons per minute (GPM), which is suitable for serving multiple fixtures simultaneously. Additionally, its 99.8% energy efficiency rating makes it an economical option, as it minimizes energy waste and reduces utility bills.

The Rinnai RE199eP is a propane-powered outdoor tankless water heater designed to deliver hot water efficiently without running out. It offers a strong flow rate of up to 9.8 gallons per minute, enough to supply several fixtures at once, which is great for larger households or homes with multiple simultaneous water demands. The heater runs on liquid propane and boasts a high heat output of 199,000 BTU, capable of heating water up to 140°F, making it suitable for colder climates where a significant temperature rise is needed. Its compact size, roughly the footprint of a small suitcase, helps save space in outdoor installations.

The Rinnai RX130iN tankless water heater is a versatile choice for anyone needing a reliable source of hot water without the bulk of a traditional tank. It delivers up to 7.1 gallons per minute, meaning it can comfortably supply hot water to multiple fixtures at once, which is great for larger households. This model runs on natural gas or propane, making it flexible depending on your fuel preference or availability. Its energy efficiency is excellent, with a high UEF rating of 0.97, so it uses fuel very efficiently, helping keep utility costs lower.