10 Best Tankless Water Heaters of 2026: Efficient Picks for Faster Hot Water

Tankless water heaters can deliver hot water on demand, reduce standby energy loss, and free up space compared with bulky storage tanks.

To help you choose the right fit, this roundup focuses on performance, fuel type, flow rate, efficiency, and installation needs across a range of home sizes.

Best 10 Tankless Water Heaters Picks for 2026

Compact Electric Pick – Rheem RTEX-13 13kW Tankless Water Heater

If you want one of the more compact tankless water heaters for point-of-use or smaller whole-home needs, the Rheem RTEX-13 is built around simple electric operation and easy temperature control. It offers on-demand hot water with a digital display, side water connections, and a straightforward wall-mounted design.

Best For: Smaller households or applications that need a compact electric tankless water heater with easy temperature adjustment.

Pros:

• External digital thermostatic control with LED display and 1-degree adjustments
• 99.8% energy efficient electric operation with self-modulating power control
• Compact wall-mount design with included 1/2 NPT adapters for simpler installation
• Copper immersion heating elements are field serviceable

Cons:

• Requires 240V power and 54A electrical capacity
• Lower flow rate than larger whole-home units, at up to 3.17 GPM
• Installation still depends on proper electrical setup

This model makes sense if you want a space-saving electric tankless water heater with basic controls and strong efficiency, but it is best matched to homes and fixtures that fit its electrical and flow requirements.

Flexible Gas Flagship – Rinnai RX160iN Condensing Smart Sense

The Rinnai RX160iN is a premium choice among tankless water heaters if you want gas-powered flexibility and high output in a compact cabinet. It can be installed indoors or outdoors, works with natural gas or propane, and is designed to deliver up to 9 GPM for multiple fixtures at once.

Best For: Homes that need a high-capacity gas tankless water heater with indoor/outdoor installation flexibility.

Pros:

• Supports natural gas or propane with Smart Sense gas control
• Indoor or outdoor installation capability with Versa Vent
• Up to 9 GPM, suitable for multiple fixtures at once
• Very high efficiency with UEF .97 and a Quick Flush feature

Cons:

• Professional installation is recommended
• Outdoor installation requires the RX-OVC vent cap
• WiFi control needs the separate Controlr module

If you want a versatile gas unit that balances strong performance, compact size, and installation flexibility, this Rinnai is one of the most capable tankless water heaters in the group.

High-Output Electric Upgrade – Rheem RTEX-24 24kW Tankless Water Heater

The Rheem RTEX-24 is aimed at buyers comparing tankless water heaters for stronger electric performance and whole-home convenience. It is a wall-mounted 24kW unit with digital temperature control, no venting requirement, and a compact footprint that saves space over a traditional tank.

Best For: Larger households that want a higher-capacity electric tankless water heater with no venting.

Pros:

• Up to 5.9 GPM for multiple fixture applications
• Digital thermostatic controls in 1-degree increments from 80°F to 140°F
• No venting required, which simplifies installation versus gas models
• Compact wall-mounted design saves space

Cons:

• Requires substantial electrical capacity, including three 40-amp double-pole breakers
• Needs a recommended minimum 200-amp household service panel
• Higher installation planning burden than smaller electric units

This is a strong option if you want an electric tankless water heater with more output than entry-level models, but it only makes sense when your home’s electrical system can support it.

Budget-Friendly Propane Choice – Ranein 3.6 GPM Indoor Tankless Heater

The Ranein propane model is a practical pick for shoppers comparing tankless water heaters for a smaller gas setup with strong safety features. It delivers 80,000 BTU, supports 2 to 3 water points, and includes temperature controls and preset modes designed to make daily use simpler.

Best For: Smaller propane setups that need on-demand hot water, preset modes, and added safety features.

Pros:

• 80,000 BTU output with 3.6 GPM for 2-3 water points
• Adjustable 95°F to 149°F temperature range with intelligent control
• Child lock and four preset modes for family-friendly use
• Includes vent pipe and built-in anti-freeze protection

Cons:

• Not intended for elevations above 2,000 feet
• Requires licensed professional installation
• Lower flow rate than larger whole-home gas models

For buyers who want a compact propane tankless water heater with useful safety protections and an included vent pipe, this Ranein model offers solid value as long as the installation limits fit your home.

Whole-Home Electric Pick – Rheem 18kW 240V Tankless Electric Water Heater

If you want a compact electric option in the tankless water heaters category for steady whole-home use, this Rheem 18kW model is built around simplicity and control. It offers external digital temperature adjustment, self-modulation, and up to 4.4 GPM, making it a practical fit for households that want efficient on-demand hot water without a large footprint.

Best For: Homes that want a wall-mounted electric tankless water heater with precise temperature control and straightforward installation.

Pros:

• External digital thermostatic control with LED display and 1-degree accuracy
• Self-modulating output adjusts power to match hot water demand
• Up to 4.4 GPM flow rate for whole-home use
• Copper immersion heating elements are field serviceable

Cons:

• Requires a 240V electrical setup
• Best suited to moderate demand rather than the highest simultaneous loads

Overall, this is a strong pick if you want an efficient electric tankless water heater with practical controls and a compact wall-mounted design. Its 99.8% efficiency and simple replacement-friendly connections add to its appeal for direct, no-fuss installations.

High-Flow Propane Choice – APUS Propane Tankless Water Heater 140,000 BTU

For shoppers comparing tankless water heaters for a busy home, this APUS propane model stands out for high flow and smart convenience. It combines a 140,000 BTU burner, up to 6.8 GPM, WiFi app control, and a built-in booster pump, making it a flexible option when you need strong whole-house hot water delivery.

Best For: Families wanting a propane tankless water heater with high flow, smart controls, and multi-fixture performance.

Pros:

• Up to 6.8 GPM with a built-in booster pump that increases flow by up to 130%
• WiFi remote control through the Tuya app
• Zero-cold-water tech and smart season comfort mode for steadier temperatures
• Eight protection systems plus freeze and overheat protection

Cons:

• Requires liquid propane and a 120V AC connection
• Drainage is required in colder conditions or long periods of nonuse

This model is a strong fit if you want a propane tankless water heater with modern controls and enough capacity to handle multiple points of use. Its compact size, quiet turbo fan design, and high UEF make it especially appealing for households that want performance and efficiency in one package.

Compact Under-Sink Option – 14kW Tankless Water Heater Electric 240V

If you need a smaller electric option in the tankless water heaters lineup, this 14kW unit is designed for sink-and-shower use with a compact footprint. It delivers up to 3.3 GPM, includes LED temperature control, and is positioned for users who want instant hot water in a space-saving wall-mounted or under-sink setup.

Best For: Smaller homes, apartments, or point-of-use installs that need a compact electric tankless water heater.

Pros:

• Compact body with flexible under-sink or wall mounting
• LED display with precise 1°F temperature adjustment
• Up to 99.8% thermal efficiency and no standby energy loss
• Safety features include leakage protection, overheating protection, and auto shut-off

Cons:

• Requires a 60-amp circuit breaker and 240V power
• 3.3 GPM flow rate is better for 1-2 usage points than large households

As an electric tankless water heater, this model focuses on efficiency, compact installation, and straightforward control. It makes sense for buyers who want fast hot water at a sink or for limited simultaneous use without the size and standby losses of a traditional tank.

Whole-Home Gas Performer – Rheem RTG 7.0 GPM Indoor Tankless

If you want tankless water heaters for a larger household, this Rheem gas model is built for steady whole-home use. It delivers up to 7.0 GPM at a 35°F rise and 160,000 BTUs, which is enough for multiple hot-water points at once when your usage is moderate. The indoor, wall-mounted design also helps free up floor space while keeping the system focused on continuous demand.

Best For: Larger families and multi-bathroom homes that need consistent on-demand hot water indoors.

Pros:

• 7.0 GPM output supports 2-3 simultaneous showers at a 35°F rise
• 0.82 UEF and on-demand heating can reduce energy use versus a 50-gallon electric tank
• Digital LED control allows ±1°F temperature adjustments
• LeakGuard, freeze protection, and flame failure protection add safety features

Cons:

• Requires natural gas and indoor direct vent installation
• Best fit for households with enough demand to justify a whole-home unit

This is a strong option if you want a gas tankless heater with high output, efficiency, and built-in safety features. It is especially practical as a replacement for an aging tank heater in a busy home.

Compact Electric Efficiency – ORBEK 14kW 240V Tankless

This electric pick is a compact option in tankless water heaters for homes that want fast hot water without a bulky tank. It provides up to 3.38 GPM and is designed to deliver hot water in about 3 seconds, with stable temperature control within 1°F. The slim wall-mounted build makes it easier to fit into tight utility spaces.

Best For: Apartments, smaller homes, or point-of-use setups that want quick electric hot water in a compact footprint.

Pros:

• 3.38 GPM output can serve 2-3 points of use
• Uses up to 60% less electricity than traditional tank heaters
• Chip-controlled heating keeps temperature stable within 1°F
• ETL certified with leakage, over-temperature, and dry-heating protection

Cons:

• Requires a 240V/60A two-pole breaker and substantial panel capacity
• Lower flow rate than whole-house gas models

For buyers who want an efficient electric unit with precise temperature control, this ORBEK model is easy to evaluate on specs alone. Just make sure your electrical setup can support the required install before choosing it.

Portable Propane Outdoor Pick – 18L Propane Tankless with Digital Display

For outdoor use, this propane model stands out among tankless water heaters because it is built for portability and quick hot water delivery. It produces up to 115,425 BTU/hour and 4.76 GPM, making it practical for camping, RV travel, pet washing, and other off-grid tasks. The digital display and compact design make it easier to set up and use on the go.

Best For: Campers, RV owners, and outdoor users who need portable on-demand hot water.

Pros:

• 4.76 GPM flow with 115,425 BTU/hour output
• Portable, lightweight design for camping and RV use
• Six safety protections, including antifreeze and flame-failure cutoff
• Digital display and adjustable temperature range for practical control

Cons:

• Built for outdoor and portable use, not indoor whole-house installation
• Maximum temperature tops out at 113°F

This is a good fit if you need a propane heater that travels well and handles everyday outdoor washing tasks. It is less about whole-home capacity and more about dependable hot water wherever you set up camp.

How We Picked the Best Tankless Water Heaters

We looked for Tankless Water Heaters that balance real-world hot water output with practical installation demands. The strongest picks offer the right mix of flow rate, temperature rise capability, energy source, and reliability for different household needs.

We also considered whether each unit is better suited for whole-home use or a point-of-use application, since the best choice depends as much on usage pattern as raw power.

Quick Comparison

Electric models are often simpler to install and work well for small homes, apartments, sinks, or low-to-moderate demand. Gas and propane units typically deliver higher flow rates, making them better for larger households or multiple simultaneous fixtures.

Condensing and high-efficiency designs can lower operating costs over time, while compact non-condensing units may be more budget-friendly upfront. Matching the heater to your climate and plumbing layout is just as important as comparing GPM ratings.

Key Buying Factors for Tankless Water Heaters

Flow Rate and Temperature Rise

Look beyond the headline GPM number. A unit’s usable output depends on incoming water temperature and how much heat it can add. Colder climates need more capacity to maintain the same shower performance.

Fuel Type and Electrical Requirements

Electric Tankless Water Heaters usually need dedicated high-amperage circuits, while gas and propane models may require venting, gas line upgrades, and more installation space. Check your home’s infrastructure before choosing.

Indoor Installation and Venting

Indoor gas units need proper venting and clearances. If you are replacing an existing tank, verify that your setup can support the new unit without major plumbing or utility changes.

Whole-Home Vs Point-Of-Use

Some Tankless Water Heaters are best for one shower, sink, or remote fixture, while others are built to handle multiple bathrooms and higher peak demand. Choose based on how many fixtures may run at the same time.

Who Should Buy Which Tankless Water Heaters?

Choose an electric model if you want a compact option for smaller homes, apartments, or single-bath use. Choose propane or natural gas if you need stronger whole-home performance, higher flow, or faster recovery for busy households.

If you want lower operating costs and plan to stay long term, efficiency and sizing matter more than the lowest purchase price. The best Tankless Water Heaters are the ones that match your actual usage, not just the biggest specs on paper.