Best tankless water heater

If you want the best tankless water heater for a typical home, I'd start with a gas-fired Rinnai or Navien. If your home is all-electric, an electric tankless unit may be an option, but it can require substantial electrical upgrades.

The best choice depends on more than brand: hot-water demand, incoming winter water temperature, fuel type, installation cost, and local service availability all matter.

My top tankless water heater picks

(Best overall)

Rinnai Sensei RX199iN

$1,533–$1,703

Approximate unit price

My first choice for a gas-powered home. High efficiency (0.98 UEF), strong output, and a good fit for households that run multiple fixtures. TanklessHeaterLab homedepot.com

Best if you want a premium, long-term installation.

View at Home Depot

Navien NPE-240A2

About $1,600–$2,000

Approximate unit price

Best if you want faster hot water at the tap. Its built-in recirculation pump and buffer tank can reduce waiting time when properly configured. Green Reviews Hub Tankless Geek

Best for busy households with long pipe runs.

View Navien models

Rheem Performance Platinum 9.5 GPM

About $1,100–$1,500

Approximate unit price

A strong value pick for a typical two- or three-bathroom home. It offers substantial output without necessarily paying for premium features. Green Reviews Hub TanklessHeaterLab

Browse Rheem tankless heaters

Stiebel Eltron Tempra 36 Plus

$849.00

Unit price at The Home Depot

My electric pick for homes with sufficient electrical capacity. It is a 36 kW unit, but in a cold climate like Michigan, its usable hot-water flow can be much lower than its headline rating suggests. Bob Vila TanklessHeaterLab

Important: check your electrical panel and service capacity first.

View product and current price

What I'd budget

For a professionally installed whole-house gas tankless system, a rough planning budget is $3,000–$6,000 or more, depending on whether you need new venting, gas-line upgrades, condensate drainage, or plumbing changes. Electric installations can also become expensive if your panel or service needs upgrading.

Before buying, have the installer size the unit for your winter incoming-water temperature and the number of showers and faucets likely to run at once. Advertised maximum GPM is not the same as the flow you'll get in Michigan in January.

Let me narrow it down to the best one for your home

I can give you a more confident recommendation with just a little information.

1. What fuel does your current water heater use?

Natural gas

Propane

Electric

Not sure

2. How many bathrooms do you have?

1 bathroom

2 bathrooms

3 bathrooms

4 or more bathrooms

3. What's most important to you?

Reliability and long life

Lowest purchase and installation cost

Maximum hot-water capacity

Energy efficiency

Fast hot water at the faucet

4. What's your total installed budget?

Under $2,000

$2,000–$4,000

$4,000–$6,000

Over $6,000

[Find my best match]

The best tankless water heaters depend on your fuel type, home size, and climate, with top picks leading the market across gas and electric categories.

Best Natural Gas & Propane Tankless Water Heaters

Delivers high-efficiency condensing performance with up to 10 to 11.1 GPM flow rates, dual stainless steel heat exchangers, smart connectivity, and optional built-in recirculation pumps. www.bobvila.com

Features a 0.93 Uniform Energy Factor (UEF), built-in Wi-Fi controls, and PVC venting compatibility that cuts down installation time.

Frequently praised by plumbers for stainless steel components and built-in recirculation, though mixed user reliability notes exist online. Reddit Modernize Home Services

Best Electric Tankless Water Heaters

商品图片 Rheem RTEX-13 $250.00 $340.00 Miami Water Heater& more 4.4 (118) c040cc57c2c8b48e7607621f658d66e3

Offers ~99% efficiency, up to 7.5 GPM output, and Advanced Flow Control to eliminate cold water fluctuations. YouTube

商品图片 EcoSmart Eco 27 $549.00 $579.99 Acme Tools& more 4.07 (603) 8d19eb65d2e7826e0347d45f9f05cba6

A compact, self-modulating unit providing up to 3.51–8.8 GPM depending on model scale, ideal for smaller setups or point-of-use application. YouTube

A popular 27 kW, 240V self-modulating option well-suited for whole-home use in warmer regions. JustAnswer

You can check out a wide selection of top-rated choices or request installation guidance directly through The Home Depot Tankless Water Heaters. The Home Depot

See a detailed breakdown of top gas and electric models compared side-by-side:

To narrow down the best model for your home, let me know:

Is your supply natural gas, propane, or electric ?

How many bathrooms or fixtures run hot water at the same time?

What is your general region or climate (cold winters vs. warm climate)?

Choosing the "best" tankless water heater depends heavily on your home’s fuel source (gas vs. electric), your household's peak hot water demand, and your climate.

The top-performing tankless water heaters on the market are categorized below by type and use case:

1. Best Gas Tankless Water Heaters (Whole-Home)

Gas units generally offer the highest flow rates, making them ideal for standard-to-large homes running multiple showers or appliances at once.

• Best Overall / Premium: Navien NPE-240A2
  • Why it stands out: Navien is widely praised by plumbers for its dual stainless steel heat exchangers and built-in ComfortFlow recirculation system (which includes a small buffer tank and pump). This virtually eliminates the annoying "cold water sandwich" effect and delivers hot water almost instantly. Western Rooter
  • Best for: Larger households that want luxury features, top-tier energy efficiency (high UEF), and built-in recirculation. Hillside Oil Heating & Cooling
• Most Reliable / High Capacity: Rinnai RU199iN Hillside Oil Heating & Cooling
  • Why it stands out: Rinnai is an industry titan known for exceptional longevity. Modernize The RU199iN is a condensing powerhouse capable of delivering up to 11 gallons per minute (GPM), meaning it can easily handle 5 to 7 fixtures simultaneously. Hillside Oil Heating & Cooling It also features Wi-Fi readiness and a compact design. Western Rooter
  • Best for: Big families or high-demand homes needing commercial-grade output in a residential footprint. Western Rooter
• Best Value & Smart Tech: Rheem RTGH-95DVLN
  • Why it stands out: Rheem strikes an incredible balance between price, professional reliability, and user-friendly tech. Modernize It includes EcoNet compatibility for smart-home integration, low-flow activation, and strong condensing efficiency. Hillside Oil Heating & Cooling
  • Best for: Homeowners looking for a smart, highly efficient gas unit that is easy for local contractors to service. Modernize

2. Best Electric Tankless Water Heaters

Electric tankless units require significant electrical infrastructure (often requiring multiple 240V dedicated breakers and heavy-gauge wiring upgrades), but they are great if you don't have a gas line.

• Best Whole-Home Electric: Stiebel Eltron Tempra Series (e.g., Tempra 36 Plus)
  • Why it stands out: Stiebel Eltron is a gold standard for German-engineered electric tankless systems. Their Advanced Flow Control automatically modulates power and flow so that you never experience sudden temperature drops when someone opens another faucet.
  • Best for: Whole-home electric setups where precise temperature stability is a must.
• Best Budget Electric Option: EcoSmart ECO 27 / ECO 36 Western Rooter
  • Why it stands out: EcoSmart units use self-modulating technology to scale energy consumption based on how much hot water you are pulling. They are compact, budget-friendly upfront, and widely available. Western Rooter
  • Best for: DIY-savvy buyers or homeowners looking for a cost-effective whole-home electric retrofit (though ensure your electrical panel can handle the amperage).

Quick Buying Checklist Before You Choose:

1. Fuel Source: Gas units generally outperform electric models in colder climates because they can handle a higher "temperature rise" (the difference between your incoming groundwater temperature and your target hot water temperature).
2. Sizing (GPM): Calculate your peak load. Add up the flow rates of everything you might run at once (e.g., a shower uses about 2.0–2.5 GPM, a kitchen sink uses 1.5 GPM).
3. Venting and Drainage: Condensing gas tankless heaters require specific PVC, CPVC, or stainless steel venting and a drain for acidic condensate water. Ensure your installation space permits this.

What type of fuel (gas or electric) do you plan to use, and roughly how many bathrooms or simultaneous fixtures do you need to support?

For most homes with natural gas, the Rinnai RX180iN is a strong pick: reviewers name it their top choice for efficiency, up to 10 GPM flow, and straightforward controls. The best model for your home depends on fuel type, incoming-water temperature, and how many fixtures may run at once; for electric, the Stiebel Eltron Tempra 36 Plus is a leading pick.bobvila.com

There is no single “best” tankless water heater—it depends on your fuel type (gas vs. electric), household size/simultaneous demand, climate (incoming water temperature), budget, and features like recirculation. Proper professional sizing and installation matter more than the brand in many cases. consumerreports.org

Top Recommendations (2026 Consensus)

Best overall for most homes with natural gas or propane
Rinnai Sensei RX199iN (or similar high-end Sensei RX/RXP models)

• Up to ~11.1 GPM (warm-climate max; real-world lower in cold water), 199,000 BTU, 0.98 UEF (very high efficiency).
• Condensing, dual-fuel (natural gas or propane via Smart Sense, no conversion kit needed), indoor/outdoor flexible install.
• Strong reliability reputation, solid service network, WiFi-capable (module often extra), 15-year heat exchanger warranty (with registration).
• Street price roughly $1,500–$2,000 for the unit.
  Many recent reviews and plumber comparisons rank this (or the broader Sensei line) as the top pick for capacity, efficiency, and long-term durability. thefurnaceoutlet.com

Best if you want built-in recirculation (near-instant hot water at fixtures)
Navien NPE-240A2

• Similar high capacity (~11.2 GPM max) and efficiency.
• Built-in recirculation features (ComfortFlow with buffer tank on A2 models) are a standout.
• Strong efficiency and quiet operation; 15-year heat exchanger warranty.
• Slightly higher unit cost in many comparisons; excellent for larger or multi-bath homes that want to minimize wait times. tanklessheaterlab.com

Best value / widely available gas option
Rheem models (e.g., RTG series non-condensing or Performance/Prestige/Ikonic condensing lines, such as higher-GPM outdoor or indoor units around 7–9.5+ GPM)

• Solid performance, broad retail/plumber availability (Home Depot, etc.), competitive pricing, and good warranties (often 15 years on heat exchanger for higher models).
• Easier to source parts and service in many areas. Lower efficiency on non-condensing models (~0.82 UEF) vs. premium condensing units.
• Frequently called out as a strong budget-to-midrange choice. www.thisoldhouse.com

Best electric whole-home
Stiebel Eltron Tempra 29 Plus (or larger Tempra 36 Plus)

• Excellent temperature consistency thanks to Advanced Flow Control.
• High quality (German engineering), high efficiency.
• Needs substantial electrical service (typically multiple 40A breakers and often 200A+ panel for whole-home models). Not ideal for older homes with limited electrical capacity.
• Smaller Rheem RTEX series (e.g., 13–18 kW) work well for apartments, point-of-use, or milder climates/lower demand. www.theconsumers.guide

Bosch ranks highly for brand trust in consumer surveys. www.lifestoryresearch.com

Key Buying Factors

• Sizing (GPM): Calculate based on simultaneous fixtures + your groundwater temperature. Manufacturer max GPM assumes warmer inlet water; performance drops significantly in cold climates. A professional should size it.
• Gas vs. Electric: Gas generally better for higher whole-home demand. Electric is simpler (no venting/gas line) but power-hungry and limited by your electrical panel.
• Efficiency & costs: Condensing gas models (0.93–0.98 UEF) save the most on energy. Expect higher upfront + installation costs ($1,000–$3,000+ install common) vs. tank units; payback depends on usage and local rates. High-efficiency models may qualify for federal tax credits.
• Maintenance: Annual descaling is important in hard-water areas. Condensing units need condensate drainage.
• Other: Recirculation pump (built-in or add-on) for instant hot water; WiFi/app control; local code/venting/gas-line requirements.

Consumer Reports testing has found that leading gas and electric tankless models perform similarly on basic hot-water delivery; differences show up more in efficiency, features, durability, and serviceability. consumerreports.org

Recommendation process: Get quotes from licensed plumbers experienced with tankless systems. They should evaluate your gas line/venting/electrical capacity, groundwater temps, and peak demand. Avoid purely cheapest online options without professional install—improper setup is a common source of problems.

If you share details (gas or electric? number of bathrooms/people? climate/region? budget? need for recirculation?), I can refine this further.