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How much does tankless water heater installation cost?

Installing a tankless water heater costs $1,400 to $5,600 on HomeGuide's published range — $2,100 to $5,600 for gas, $1,400 to $3,000 for electric.

The cross-checks bracket the same territory rather than repeating it. Fixr's national average is $2,811 on a range of $2,500 to $4,500. NerdWallet publishes $1,400 to $3,900 including installation, and notes Home Depot lists its average tankless installation at $4,300. Different databases, one message: this is a four-figure job, and the fuel type decides which half of the band you are in.

Sources: HomeGuide, Fixr, NerdWallet

This page is general information, not professional advice. Prices move with your home, your region and the season, and the only number that counts is a written quote from a licensed plumber who has looked at the job.

What the total is made of

LinePublished cost
The tankless unit$600 – $2,600
Installation labor (3 – 10 hours)$600 – $2,500
Supplies: pipes, connectors, valves$150 – $300
Permits$50 – $200
Total installed$1,400 – $5,600
HomeGuide's published breakdown of a tankless installation. The unit itself is only 40% to 45% of the project, on its figures.

Source: HomeGuide

Why the labor line is so wide: the upgrades. HomeGuide prices a new dedicated electrical circuit at $250 to $900, a larger gas supply line at $350 to $2,000, and first-time venting for a gas unit at $500 to $1,500. A house that already has the gas line and the venting skips most of that, which is exactly the question to ask before believing any quote.

Source: HomeGuide

Tankless water heater replacement cost

Swapping a worn-out tankless unit for a new one costs less than a first conversion, because the gas line, venting and mounting already exist. The published band is the same $1,400 to $5,600, but HomeGuide notes same-for-same replacements are typically cheaper than retrofits that need plumbing or electrical modifications — your job should price toward the bottom of its fuel's band.

Sources: HomeGuide, HomeGuide

Is tankless worth it against a tank?

HomeGuide's own comparison: a standard tank costs $600 to $3,100 installed and lasts 8 to 12 years, while a tankless unit costs $1,400 to $5,600 and lasts 15 to 20. On running costs it publishes $220 to $480 a year for gas tankless against $250 to $420 for a gas tank, and $340 to $540 for electric tankless against $530 to $600 for an electric tank.

Source: HomeGuide

So the honest arithmetic is upfront money against lifespan and monthly burn. A household that runs out of hot water every morning buys something real. A one-person household mostly buys a longer warranty period on a pricier box.

To put your own size and fuel into the published tables and see both totals side by side: the water heater cost calculator.

Questions people ask next

How much is a gas tankless water heater installed?
HomeGuide publishes $2,100 to $5,600 for a gas tankless unit including labor and required modifications. Gas runs higher than electric because of the gas line, combustion venting, and the extra labor hours those bring.
How much is an electric tankless water heater installed?
HomeGuide publishes $1,400 to $3,000 installed and calls electric units cheaper and easier to install than gas. The catch is capacity — the electrical panel has to carry the load, and HomeGuide prices a new dedicated circuit at $250 to $900 if yours cannot.
How long does tankless water heater installation take?
HomeGuide says 3 to 10 hours of labor depending on the upgrades involved, and Fixr reads 6 to 10 hours at $75 to $130 per hour. A first-time conversion from a tank sits at the long end; a same-for-same swap at the short end.
Does a tankless water heater need a permit?
Commonly yes — HomeGuide lists permits at $50 to $200 as a standard line of the project. The rules and the fee are set by your city's building department, and they differ enough by place that we wrote a separate page on water heater permits.

Written for homeowners by Most Recommended Plumbers, which measures which plumbers AI assistants actually recommend in 26 U.S. metros. Nobody can pay to be on those lists. How we measure.

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