Bob Vila cites a typical installed range of $1,333 to $3,721 for a tankless water heater, with a national average of $2,527. Those figures include the unit and the labor, and they leave out surprises behind the walls. The rest of this page separates the bill into parts so a quote from a Westside plumber is easy to compare. For the repair side of hot water, head to water heater repair first.
How much will the tankless install itself run?
Bob Vila reports $1,333 to $3,721 as the usual installed range and $2,527 as the national average. By fuel, electric units run $800 to $1,500 and natural gas or propane units $1,000 to $1,500 in that guide, materials and labor together. The figure for your own house comes only from a written quote.
Spread comes from three places. The unit itself ranges widely by brand and capacity: the guide's per-unit prices go from $280 to $2,600. Labor usually totals $600 to $1,850. And the add-ons, covered below, can change the answer more than the model does. When two quotes differ by a thousand dollars, the gap is almost always venting, gas line or electrical work, not the heater.
Where does the labor money go?
Plumbers bill $45 to $200 hourly in that guide, which adds up to $600 to $1,850 on a typical job, and an electrician charges $50 to $100 per hour for two hours at most. A plain tank swap, per Bob Vila's other guide, carries labor of $150 to $450.
That difference is the point. A tankless install is a bigger job: mounting on a wall, new venting, connecting gas and water, often a condensate drain, and a test. Swapping like for like is faster. Request labor as a separate line, which shows whether the hours are realistic. Hard-to-reach locations such as attics, tight closets or finished-wall runs add labor.
What extras should I budget for?
Plan for a gas line upgrade, which the guide says can add up to $1,000, electrical updates if a circuit is needed, venting, a permit of $50 to $100, removal of the old heater from $500, and about $10 per foot for pipe and insulation. Not every item applies to every home, though many do.
The gas line matters because a tankless heater pulls a large volume of gas in bursts, and the existing pipe may be too narrow. Gas piping is regulated work, done by a contractor under a permit, as the gas line page explains. Moving from gas to electric may mean panel work as well. Before approving a bid, ask which of these extras are in the number and which are not.
Is a tankless heater a better deal than a tank unit?
Not on installed price alone. Bob Vila's water heater installation guide puts electric tank units at $600 up to $3,500 and gas tank units from $700 to $2,700, materials and labor combined. Tankless tends to cost more at the start and may save on energy later, so the comparison turns on years of use.
Running costs in the tankless guide are about $200 a year on natural gas and $350 on propane, and electricity is left out because rates vary. Whether that beats the current heater hinges on household size and the years you expect to stay. The tank versus tankless page lays out the trade-offs, and water heater replacement cost has the tank side in more detail.
What do tank replacement jobs cost by size and part?
In Bob Vila's installation guide, replacement labor runs $150 to $450 and a permit $25 to $300, with a gas line permit adding $50 to $300; hauling off the old heater costs $100 to $500. Prices by tank size sit in a chart image rather than text, so a quote is the way to price the common sizes, 40 and 50 gallons.
Parts you may be asked to replace, with Fixr's guide figures, labor included:
| Part or job | Fixr guide range |
|---|---|
| Heating element | $200 - $750 |
| Anode rod | $125 - $300 |
| Pressure relief valve | $100 - $250 |
| Gas valve | $150 - $300 |
| Thermostat replacement | $100 - $250 |
For parts, the anode rod replacement, heater element replacement and relief valve replacement pages explain each job. An anode rod swap is often cited as a way to extend tank life, but a plumber should judge whether your tank is worth keeping.
Do I need a permit in Santa Monica or Los Angeles?
Plan on one. Santa Monica's homeowner guide names hot water heater change-outs among plumbing jobs covered by a Single Trade Permit, which the owner, or a contractor holding a state license, may take out. Los Angeles neighborhoods go through that city's building department, whose site has current steps.
The permit fee is separate from labor. An inspection follows, and the city's guide says approval is needed before work gets covered. Practical steps live in the water heater permit guide. While collecting quotes, find out who files the permit and if its fee is in the total.
How do I compare tankless quotes fairly?
Give every bidder one checklist: model and capacity, venting type and route, gas line size, electrical work, permit, hauling the old heater away, and any warranty. A bid that names none of those cannot be compared with one that names all, and an unusually low total invites the question of what was left out.
Above $1,000, California's contractor rules apply, and a deposit is limited to 10 percent or $1,000, whichever is smaller; half in advance deserves pushback. The state's online lookup shows license status. Through Sunset Coast Plumbing, the price arrives in writing ahead of a local plumber's visit, and the tankless installation service page describes how it goes.
Common questions
Are there free estimates for water heater repair or replacement?
Policies differ: some businesses estimate a replacement for nothing yet charge to diagnose a repair, and we cannot speak for any single company. Ask in advance about any diagnostic fee and whether it comes off the repair bill. Describing the unit on the quote page keeps the estimate close to the real job.
What does a gas valve or relief valve replacement cost?
Fixr shows $150 to $300 for a gas valve and $100 to $250 for a relief valve, labor included. Hard access or a gas permit raises it. A relief valve that leaks can signal high pressure or thermal expansion, so a good plumber finds the cause before swapping the part.
Is the smaller tank cheaper?
The guides checked for this page give no size-by-size dollar figure in text, so none is invented here. Larger tanks generally cost more, and the right capacity follows how many people draw hot water together. Ask for a quote that lists 40 and 50 gallons side by side.
Will a tankless unit work with my existing gas line?
Sometimes. These heaters draw a heavy flow of gas, and an undersized line must be upgraded, which Bob Vila says can add up to $1,000. The plumber checks pipe size and run length and reports back before any work. Because gas piping is regulated, a contractor does it under a permit.
Sources used
Page updated