Replacing a failing tank or upgrading for faster hot water? The best tankless electric water heaters deliver on-demand hot water, lower energy bills, and a smaller footprint—perfect for busy bathrooms and kitchens.
This guide compares the best tankless electric water heaters by flow rate, energy efficiency, durability, and ease of installation so you can choose the right whole-house or point-of-use model for long showers, family demand, or tight spaces.
Best Overall: EcoSmart ECO 11 13kW Tankless Electric Heater — compact, energy-saving self‑modulating unit with steady flow
Best Budget: Rheem 11kW Tankless Electric Heater — low-cost point-of-use option for a single fixture
Best Premium: CAMPLUX 6kW Point-of-Use Tankless Heater — precise temp display and fast warm-up for under-sink installs
Best for Long Hours: ORBEK 14kW On-Demand Tankless Heater — robust output and durability for extended use
Buying Guide
Capacity and flow rate (GPM)
Match the unit’s output to how many fixtures you expect to run at once. Tankless electric heaters are rated by how many gallons per minute (GPM) they can raise to a comfortable temperature. Point-of-use models cover a single sink or shower, while whole-house units support multiple showers, a washing machine and a dishwasher running together. If you value compact, space-saving designs elsewhere in your home, see best compact office chairs.
- Estimate demand: list the fixtures you’ll run simultaneously and check typical flow rates for showers and faucets.
- Consider temperature rise: colder incoming water needs more power to reach the same outlet temperature—choose a higher-capacity unit in colder climates.
- Example: a compact option like the EcoSmart ECO 11 is well suited for single fixtures or light simultaneous use thanks to its modest kW rating.
Power and electrical requirements
Electric tankless heaters run on 240V and different kW ratings demand different circuit sizes and wiring. Before buying, check your electrical panel capacity, available breaker slots and your home’s overall service rating.
- Higher kW units give higher flow rates but require heavier gauge wiring and multiple breakers—verify installation costs if you need panel upgrades.
- Confirm whether the unit needs dedicated breakers and how many; some whole-house models require several breaker spaces.
- Example: the Rheem 18kW Electric Tankless is a typical 240V option that illustrates how mid-to-high kW units affect electrical planning.
Installation type and location
Decide whether you want a point-of-use unit near a fixture or a single whole-house unit. Point-of-use heaters minimize lag and heat loss and are easier to install for individual sinks; whole-house units simplify maintenance but may need more complex electrical work.
- Point-of-use units are compact and often install under sinks or in closets—look for clear indoor installation guidance and CSA/ETL approvals.
- Whole-house installations should be positioned to minimize long hot-water runs for best performance and efficiency.
- Example: the CAMPLUX 6kW is designed for under-sink, point-of-use applications with a temperature display and compact footprint.
If workspace layout matters to you, our guide to best office chairs for standing desk covers footprint and placement tips.
Controls, features and usability
Modern tankless units offer features that improve comfort and convenience: digital temperature displays, self-modulating elements that adjust power to demand, and smart connectivity for remote control and diagnostics.
- Self-modulating units help stabilize water temperature under varying flow conditions and can improve efficiency.
- Temperature displays and easy-to-use controls reduce guesswork during setup; Wi‑Fi or smart-home integration can be handy if you want scheduling or remote monitoring.
- Example: smart-enabled models like the Westinghouse 14kW Smart show how Wi‑Fi and voice-assistant support add convenience for some users.
For inspiration on intuitive, ergonomic controls in other products, check best ergonomic task chairs.
Durability, certifications and maintenance
Focus on build quality, certifications and a clear maintenance plan. Look for ETL/CSA listings, corrosion-resistant components, and an accessible warranty. Regular descaling and checking filters extend life, especially in hard-water areas.
- Check manufacturer warranty terms and what is covered (heating elements, parts, labor) and whether extended warranties are available.
- Certifications (ETL, CSA) confirm safety testing; IP ratings matter if the unit will be installed in damp locations.
- Plan for maintenance: many tankless electrics need periodic flushing or scale prevention measures—budget for that in your decision.
For durable, easy-care options in a different category, see best ergonomic mesh chairs.
FAQ
Are tankless electric water heaters better than traditional tank heaters?
Tankless electric water heaters heat water on demand, so they eliminate standby heat loss and save space compared with storage tanks. For many households that use hot water intermittently, that can translate to lower energy bills over time. They also tend to have longer service lives if maintained properly, but they usually cost more up front and can require electrical upgrades. Overall, they’re a good choice if you want continuous hot water and can size the unit and electrical supply correctly.
Can a tankless electric water heater supply an entire house?
Yes — but only if you choose a high‑capacity, whole‑house model rated for the flow and temperature rise you need. Larger units such as the 36kW Tankless Electric Water Heater advertise whole‑house performance and higher GPM for simultaneous showers and appliances. Climate matters: colder incoming water means you need more kW to reach hot temperatures at the same flow. Before buying, match the unit’s GPM and temperature‑rise specs to your peak hot‑water demand and consult an electrician for the required electrical service.
What size tankless electric heater do I need for a 1–2 person household?
Start by listing the fixtures you’ll run at once (shower, sink, etc.) and add their flow rates to estimate peak demand, then calculate the temperature rise needed from your incoming water to your desired output. Many small households are well served by 11–13 kW point‑of‑use models for a single shower or one to two fixtures in warmer climates. For a compact, commonly recommended option, consider the EcoSmart ECO 11 (13 kW), but always compare its specs to your calculated needs. If you live in a cold region or expect simultaneous showers, size up or choose a whole‑house unit instead.
Do I need a professional electrician to install a tankless electric water heater?
Most whole‑house electric tankless heaters require high‑amp circuits and multiple breakers, so a licensed electrician is strongly recommended to ensure safe wiring and code compliance. Some lower‑kW, point‑of‑use models can be installed by a competent DIYer if local codes allow and you have the correct breaker and wiring, but permits are often required. Manufacturer installation guides vary by model, so follow them closely and pull any required permits. When in doubt, hiring a pro avoids safety risks and potential inspection issues.
How often should I descale and maintain a tankless electric water heater?
Maintenance frequency depends on water hardness: in hard‑water areas plan to descale and flush the unit at least once a year, while in soft‑water areas every 2–3 years may suffice. Regular maintenance should include flushing the heat exchanger, cleaning or replacing inlet filters, and checking electrical connections per the manual. Using a descaling solution or white vinegar for flushing is common, but always follow the manufacturer’s recommended procedure. Keeping up with maintenance improves efficiency and extends the unit’s lifespan.
Final Verdict
After comparing the top tankless electric units, the strongest products stood out by providing steady temperature under varying flow, accurate self‑modulating controls, and the right kW capacity for real household demand. Prioritize correct kW sizing for your climate, dependable temperature control, installation footprint, and certification/quality of components. The best performers shared simple, durable control systems and consistent heat delivery that prevent wide temperature swings while keeping energy use efficient. Also consider layout and ergonomics—see our roundup of best task chairs for guidance on durable, simple controls.
🏆 Best Overall: EcoSmart ECO 11 13kW Tankless Electric Water Heater
💰 Best Budget: Rheem 11kW 240V Tankless Electric Water Heater
⭐ Best Premium: CAMPLUX 6kW Point of Use Tankless Electric Water Heater
Write Your Review
No reviews yet. Be the first to share your experience!