Tankless Water Heater Installation Cost

Installed cost by fuel

Other publishers land in the same neighborhood. HomeAdvisor's typical range is $1,406 to $3,902, Angi's is $1,400 to $3,900, and Fixr's is $1,000 to $4,000. Fixr notes tankless units usually cost nearly twice as much as tank models.

Whole-house or point-of-use

A whole-house unit serves every fixture. HomeGuide prices those at $600 to $2,600 for the unit. A point-of-use unit serves one sink or shower and costs $150 to $250. HomeAdvisor notes small 1 to 2 GPM units start as low as $150, while whole-house units with 8 GPM or more reach about $2,000.

Point-of-use units are a good fix for one far-off bathroom. They're not a cheap way to go tankless for the whole house. See point-of-use water heaters.

What a tank-to-tankless conversion adds

This is where quotes split. HomeGuide's add-on costs:

HomeGuide puts the labor at 3 to 10 hours. Angi's range for converting tank to tankless labor alone is $150 to $2,500.

Gas line. A gas tankless unit burns far more gas at full fire than a tank, and the old line is often too small. That's the most common surprise on a gas conversion.

Venting. A tankless unit can't reuse the old tank's flue. Condensing units vent through plastic pipe, and non-condensing units need stainless vent. HomeGuide says non-condensing units cost about 25% less to install than condensing ones.

Electrical. Whole-house electric tankless units need serious capacity. HomeAdvisor says they need at least 240V, 80-amp hard-wired service and a home with at least 150-amp service. In an older house, that can mean a panel upgrade on top of the heater.

What moves the price

• Fuel. Electric installs cost least, natural gas most.
• Location. Hard-to-reach or cramped spots can add 10% to 15% to labor, per HomeAdvisor.
• Size. More flow means a bigger unit and often a bigger gas line.
• Hourly rates. Plumbers or HVAC techs charge $75 to $150 an hour, and electricians $50 to $130 plus a service call fee.
• Brand. HomeAdvisor's average brand ranges run from $150 to $1,600 for EcoSmart up to $900 to $3,000 for Takagi, with Rinnai at $500 to $2,300.

Running cost and upkeep

HomeGuide puts the yearly running cost of a tankless heater at $220 to $480 on gas and $340 to $540 on electric. Budget for descaling too, especially on hard water. HomeGuide's figures for a professional flush and descale run from $75 to about $350. It's a DIY job if you're handy, with a pump, hoses and vinegar. See tankless flush.

On tax credits: the federal Energy Efficient Home Improvement Credit only covers property placed in service before December 31, 2025, per the IRS. Some cost guides still list it, but a unit installed this year doesn't qualify. Ask your gas utility about local rebates.

How to get a fair quote

Ask for three written quotes, and have each one list the model and flow rating, the gas line size or electrical work, the venting material and length, the permit and haul-away. A quote that skips the gas line on a conversion either checked your line already or will add it later. Ask which.

If the gas line, venting and panel all need work, compare the total against a new high-efficiency tank or a heat pump water heater. Sometimes tankless is still the right call. Sometimes the tank wins on cost.