Best Electric Tankless Water Heaters: Top Picks for 2026

Every homeowner has faced the frustration of running out of hot water right in the middle of a shower or while washing dishes. Traditional water heaters, especially tank models, often struggle to keep up with demand, particularly in busy households. Thankfully, electric tankless water heaters offer a modern solution, delivering a continuous supply of hot water while taking up less space.

A great electric tankless water heater combines efficiency, performance, and reliability. The best models are designed to provide on-demand hot water, ensuring that you never run out, regardless of how many fixtures are being used simultaneously. They also offer precise temperature control, energy savings, and a compact design that can fit into tight spaces.

This roundup reviews five of the best electric tankless water heaters available today, taking into account their performance, ease of installation, and user feedback. Whether you have a small apartment or a large family home, there’s a perfect model for your needs.

Here’s a quick comparison of our top picks:

Features	Rheem RTEX-24	Rheem 18kW	Stiebel Eltron Tempra 24	NOVIEEX 18kW	Rheem 11kW
Power Rating	24kW	18kW	24kW	18kW	11kW
Flow Rate	5.9 GPM	4.4 GPM	Continuous Flow	4.9 GPM	2.68 GPM
Temperature Control	80°F – 140°F	80°F – 140°F	68°F – 140°F	77°F – 140°F	80°F – 140°F
Installation Type	Indoor	Indoor	Indoor	Indoor	Indoor
Ideal Use Case	Multiple Fixtures	Small to Medium Homes	Whole House	Medium Homes	Single Fixture

Rheem RTEX-24 24kW 240V E…

The Rheem RTEX-24 is a powerful electric tankless water heater designed for families that require a steady stream of hot water. With a flow rate of up to 5.9 GPM, it’s ideal for households with multiple bathrooms or simultaneous hot water needs. This model is especially suitable for larger homes where demand is high.

What sets the RTEX-24 apart is its precise digital thermostatic temperature control, allowing adjustments in 1-degree increments from 80°F to 140°F. This feature ensures you can achieve the exact water temperature you desire, enhancing comfort and usability. Additionally, its compact design means it can fit in various locations, freeing up valuable space.

However, installation requires careful consideration of your home’s electrical capacity, needing a minimum of three 40-amp double-pole breakers and a 200-amp household service panel. This could lead to additional installation costs if your current electrical system needs upgrades.

• Power: 24kW
• Flow Rate: Up to 5.9 GPM
• Temperature Range: 80°F – 140°F
• Digital Controls: 1-degree increments
• Wiring Requirements: 240V, 3 x 40A breakers

Best for: Large households needing high hot water demand.

Rheem 18kW 240V Tankless…

The Rheem 18kW model is tailored for small to medium-sized homes, providing up to 4.4 GPM of hot water. It’s perfect for those with 2-3 fixtures running simultaneously, such as a shower and washing machine. The compact size allows for installation in tight spaces, making it a versatile option.

This unit features advanced self-modulation technology, adjusting its power output based on the hot water demand. This not only optimizes energy consumption but also maintains a consistent temperature, ensuring a reliable supply of hot water. The external digital control with LED display enhances usability, making it easy to set and monitor temperatures.

On the downside, while it serves most needs adequately, it might struggle during peak times if too many fixtures are in use simultaneously, which is a consideration for larger families.

• Power: 18kW
• Flow Rate: Up to 4.4 GPM
• Temperature Control: 80°F – 140°F
• Installation: Simple, bottom connections
• Durability: Copper immersion heating elements

Best for: Small to medium homes with moderate hot water demand.

Stiebel Eltron Tempra 24…

The Stiebel Eltron Tempra 24 is designed for homeowners who prioritize efficiency and performance. It boasts a continuous flow feature, meaning you won’t experience any interruptions in hot water supply, making it great for larger families or homes with high hot water usage.

This model is energy efficient, utilizing advanced auto-modulation technology to adjust power usage based on demand. It operates silently, which is a significant advantage if you prefer a quieter home environment. The sleek design also means it can be installed in a variety of locations without being an eyesore.

However, this unit does require a minimum of 150 amps of electrical service, which may necessitate upgrades in some homes. This can involve additional costs and planning before installation.

• Power: 24kW
• Flow Rate: Unlimited
• Temperature Range: 68°F – 140°F
• Design: Space-saving, no venting required
• Warranty: 7 years leakage, 3 years parts

Best for: Families needing uninterrupted hot water access.

18kW Tankless Water Heate…

This NOVIEEX 18kW model is engineered for efficiency, making it a solid choice for small to medium homes with multiple hot water demands. With a maximum flow rate of 4.9 GPM, it can handle several fixtures at once, such as a shower, a sink, and a washing machine.

It features an anti-scald constant temperature system, allowing for precise temperature adjustments in 1°F increments. This ensures that everyone in the household can enjoy comfortable hot water without the risk of scalding. The unit’s compact, wall-mounted design saves space, which is particularly beneficial for smaller homes or apartments.

One potential drawback is its reliance on a robust electrical system, requiring two 40A double-pole circuit breakers. Homeowners may need to consult an electrician to ensure compatibility with their existing setup.

• Power: 18kW
• Flow Rate: Up to 4.9 GPM
• Temperature Control: 77°F – 140°F
• Efficiency: 99.8% thermal efficiency
• Installation: Wall-mounted, compact design

Best for: Efficient hot water for medium homes.

Rheem 11kW Multi Fixture…

The Rheem 11kW is an excellent choice for those who need a reliable hot water source for a single fixture or in smaller spaces. With a flow rate of 2.68 GPM, it’s perfect for apartments, small bathrooms, or as a point-of-use heater in larger homes.

This model is known for its ease of installation, requiring just one 50-amp double-pole breaker and a simpler electrical setup. Its compact design makes it ideal for tight spaces, allowing for versatile placement options.

However, its lower flow rate means it might not suffice for households with higher simultaneous hot water needs. Users should consider their hot water consumption patterns to ensure it meets their requirements.

• Power: 11kW
• Flow Rate: Up to 2.68 GPM
• Temperature Range: 80°F – 140°F
• Installation: Straightforward, minimal requirements
• Best Use: Point-of-use applications

Best for: Single fixtures or small apartments.

How We Chose These Products

In selecting these electric tankless water heaters, we considered multiple factors, including efficiency, flow rate, user reviews, and installation requirements. Each product was evaluated based on its real-world performance, ensuring they meet a variety of household needs. We also examined warranty coverage and customer support options, as these are critical for long-term satisfaction.

Real user feedback was essential in our review process. We analyzed numerous testimonials to understand common issues, strengths, and weaknesses in each model. This thorough research ensures our recommendations are well-informed and trustworthy, providing you with reliable options for your hot water needs.

Buying Guide: What Really Matters

When choosing an electric tankless water heater, several key factors should guide your decision. First, consider the flow rate, which indicates how much hot water the unit can provide at once. Higher flow rates are essential for larger households with multiple hot water needs.

The power rating is also crucial. Models vary from 11kW to 24kW, affecting both performance and installation requirements. Ensure your electrical system can handle the necessary power to avoid costly upgrades. Finally, look for features like digital temperature control and energy efficiency ratings to maximize your savings and comfort.

Installation Process and Costs

Installing an electric tankless water heater requires careful planning. Most units need a dedicated electrical circuit, meaning you might need to consult a licensed electrician. Installation costs can vary widely based on your home’s existing electrical system and the complexity of the installation. Generally, homeowners should budget for both the unit itself and labor costs, which can range from a few hundred to over a thousand dollars.

Additionally, if your home lacks the necessary electrical panel capacity, you may need to upgrade, adding further to the overall cost. Always get multiple quotes and consider the long-term savings from energy-efficient models when making your decision.

Maintenance and Troubleshooting Tips

Regular maintenance of your electric tankless water heater can prolong its lifespan and maintain efficiency. Flushing the unit annually helps prevent mineral buildup, especially in areas with hard water. This simple maintenance can prevent significant issues in the long run.

If you experience inconsistent water temperature or reduced flow rates, it may indicate a problem with the heating elements or the need for flushing. Always consult the user manual for troubleshooting tips specific to your model, and don’t hesitate to seek professional help if you encounter persistent issues.

Energy Efficiency and Environmental Impact

Electric tankless water heaters are generally more energy-efficient than traditional tank models. They only heat water on demand, which reduces standby energy loss. This not only saves on energy bills but also lowers the environmental impact associated with heating water unnecessarily.

Many modern models are designed with eco-friendly features, further enhancing their sustainability. By selecting an energy-efficient tankless water heater, you’re making a positive contribution to environmental conservation while enjoying the benefits of modern technology.

Frequently Asked Questions

How do electric tankless water heaters compare to gas models? Electric tankless water heaters are usually more energy-efficient and have lower operational costs than gas models. However, gas models may provide higher flow rates in some cases.

What size electric tankless water heater do I need? The size depends on your household’s hot water demand. Calculate the flow rate needed for simultaneous use to determine the best model for your home.

Can I install an electric tankless water heater myself? While some homeowners may attempt a DIY installation, it’s highly recommended to hire a licensed electrician to ensure safety and compliance with local codes.

How often should I flush my tankless water heater? It’s recommended to flush your electric tankless water heater at least once a year, especially if you live in an area with hard water. This helps maintain efficiency and performance.

Final Recommendations

After considering various factors such as performance, size, and efficiency, the Rheem RTEX-24 stands out as the top choice for larger households needing substantial hot water. For smaller homes or apartments, the Rheem 11kW model is a fantastic budget-friendly option. Each of these electric tankless water heaters offers unique features tailored to specific needs, ensuring there’s a perfect match for every household. Explore the options and choose the best fit for your requirements.