Tankless Water Heater Cost Calculator
Tankless Water Heater Cost Calculator
The Tankless Water Heater Cost Calculator estimates the installed cost of an on-demand water heater. Choose natural gas, propane or electric, a size for your home, and whether you are replacing a tankless heater, converting from a tank or installing new, and you get a planning budget split into materials, labor, disposal, service call and permit allowance, with budget, standard and premium ranges. Gas line and electrical upgrades are priced as separate items. It is free and takes under a minute. It is a planning estimate, not a bid.
Estimate My Tankless Water Heater
Estimate your tankless water heater cost
Choose the fuel and a size based on the number of bathrooms. Then tell us what kind of job it is, where the heater will go and how soon you need it. If you are converting from a tank or installing new, you can also budget for a larger gas line or new electrical circuits. Only your ZIP code and the fuel are required.
Calculator loaded from the pre-uploaded Media file at https://www.omniestimate.com/wp-content/uploads/2026/10/030-tankless-water-heater-cost-calculator.html — this is an iframe loader, not a new upload.
How to read your estimate
The large figure at the top is the estimated project budget for a standard installation, shown as a range. Below it you will find three things:
Every figure is a planning range. Actual contractor pricing may vary based on location, conditions, material choice, labor market and project complexity.
Get Matched With Plumbers
After you calculate, use this form to be matched with local plumbers. Calculator name: Tankless Water Heater Cost Calculator. Service: Plumbing. Sub-service: Tankless Water Heater.
Lead form placeholder — form ID still needed. Shortcode placeholder: [fluentform id=”FORM_ID”] — do not submit this placeholder as a real form. After calculation, the calculator fills hidden fields and the “Get Matched With Plumbers” button scrolls to it.
Hidden fields: calculator_name, service, sub_service, estimate_low / standard / premium, material_cost, labor_cost, disposal_cost (blank for new installation), permit_cost (blank if unticked), equipment_cost (service call range), calculator_inputs, page_url and zip_code.
Planning estimate only
The Tankless Water Heater Cost Calculator provides planning estimates only. Results are not quotes, bids or guaranteed prices. Estimates are based on general US planning assumptions and do not reflect live contractor pricing or pricing specific to your ZIP code. Actual contractor pricing may vary based on location, conditions, material choice, labor market and project complexity. Gas line, venting and electrical needs are confirmed on site and can add to the cost. Rebates and tax credits are not included. Permit requirements and fees are set by your local building department. Always get written quotes from licensed, insured professionals before starting work.
What each cost category covers
Materials
The tankless heater with vent kit, connectors and fittings, plus conversion or new-location materials, gas pipe or wiring, and the add-ons you selected. Always.
Labor
Removing the old heater, then mounting, venting, connecting and testing the new one, plus any extra work. Adjusted for fuel, location and emergency timing. Always.
Disposal
Hauling away and recycling the old water heater. Replacements and conversions; not a new installation.
Service call
The trip and assessment charge. Doubled for an emergency. Always.
Permit allowance
A budget figure for the permit and inspection. It is not your actual local fee. When the option is ticked.
Removal note
Removing the old heater is part of labor, so there is no separate removal line.
How much does a tankless water heater cost?
A natural gas tankless water heater sized for a two-bathroom home typically budgets at about $3,000 to $3,550 installed. A budget installation starts near $1,850 and a premium one can reach about $5,750. These planning figures are for replacing an existing tankless heater like-for-like, indoors with easy access, in normal working hours, with a permit allowance.
If you are replacing a tank, the job costs more. Converting from a tank to the same gas tankless heater budgets at about $4,200 to $5,000. The table shows the calculator’s standard range by size and fuel for a like-for-like replacement.
| Size | Natural gas | Electric |
|---|---|---|
| 1 bathroom | $2,650 – $3,150 | $2,300 – $2,750 |
| 2 bathrooms | $3,000 – $3,550 | $2,600 – $3,100 |
| 3 bathrooms | $3,350 – $4,000 | $2,900 – $3,450 |
| 4+ bathrooms | $3,850 – $4,650 | $3,350 – $4,000 |
The next table shows how the kind of job changes the budget for a two-bathroom gas heater, at all three project levels.
| Two-bathroom gas tankless | Budget | Standard | Premium |
|---|---|---|---|
| Replace a tankless heater | $1,850 – $2,250 | $3,000 – $3,550 | $4,850 – $5,750 |
| Convert from a tank | $2,550 – $3,050 | $4,200 – $5,000 | $6,850 – $8,200 |
| Convert, with a larger gas line (up to 15 ft) | $2,800 – $3,350 | $4,600 – $5,500 | $7,500 – $8,950 |
Planning estimates from the OmniEstimate calculator. They are not quotes. Actual contractor pricing may vary.
How this calculator works
01 — Heater and labor
The calculator starts from the price of the heater size you choose and the labor to fit it, keeping materials and labor apart.
02 — Fuel and condensing
It adjusts both for fuel, adds the cost of a condensing model if chosen, and adjusts labor for where the heater goes and for emergency timing.
03 — Conversion and new work
Converting from a tank, or a new installation, adds an allowance for the extra work. A larger gas line or new electrical circuits are priced as separate items.
04 — Included items
Haul-away of the old heater and one service call are included.
The three project levels are built from different inputs for the heater, its warranty and the fittings. They are not one number multiplied up and down. Your ZIP code identifies your market for contractor matching and does not change the price.
What affects the cost of a tankless water heater?
Fuel
Natural gas is the most common fuel for whole-house tankless heaters. Propane costs slightly more: about $3,050 to $3,650 for the two-bathroom size. Electric tankless heaters are cheaper to install, at about $2,600 to $3,100, because they need no vent or gas line, but they need heavy electrical circuits and deliver less hot water in cold climates.
Size
Tankless heaters are sized by how much hot water is needed at the same time. A home with more bathrooms needs a higher-output heater, which costs more to buy and a little more to fit. The standard gas estimate runs from about $2,650 to $3,150 for one bathroom to about $3,850 to $4,650 for four or more.
Replacement, conversion or new installation
Replacing an existing tankless heater is the simplest job, because the vent, mounting and connections are already there. Converting from a tank adds about $1,150 to $1,450 for venting, wall mounting and connection changes. A new installation where there is no heater today budgets at about $4,400 to $5,300 for the two-bathroom gas size.
Gas line size
A gas tankless heater burns far more gas at once than a tank, so the existing line is often too small. A larger line adds about $390 to $480 for a run of up to 15 feet. A longer run of 15 to 40 feet moves a standard conversion to about $5,100 to $6,100 in total.
Gas Line Installation Cost Calculator — Link still needed.
Electrical supply
Whole-house electric tankless heaters need several dedicated high-amperage circuits. New circuits add about $675 to $850, moving a standard electric conversion from about $3,800 to $4,500 to about $4,450 to $5,350. An electrical panel or service upgrade, if needed, is a separate cost.
Electrical Panel Upgrade Cost Calculator — Link still needed. Dedicated Circuit Installation Cost Calculator — Link still needed.
Condensing or non-condensing
A condensing gas heater captures more heat from the exhaust, so it uses less gas and can vent through plastic pipe. It adds about $320 to $400 at standard pricing and needs a drain for condensate. A non-condensing heater costs less to buy and vents through metal pipe.
Location
A garage or utility room is the easiest place to fit a heater. A closet or tight space moves the standard two-bathroom gas estimate to about $3,150 to $3,750, and an attic or crawl space to about $3,350 to $4,050. An outdoor gas heater needs no vent, which lowers labor, and budgets at about $2,900 to $3,450. Outdoor units suit mild climates and need freeze protection.
Emergency timing
Emergency installation raises labor by about 50 percent and doubles the service call, moving the standard estimate to about $3,650 to $4,350.
Material costs
For a standard two-bathroom gas tankless heater, the calculator budgets about $1,600 to $1,950 for the heater, vent kit, connectors and fittings.
Labor costs
Labor covers removing the old heater, then mounting, venting, connecting and testing the new one. The calculator budgets about $1,100 to $1,350 for a like-for-like two-bathroom gas replacement. A conversion with a short gas line upgrade roughly doubles that, to about $2,150 to $2,650.
Add-ons, permits and disposal
| Item | Standard range | Why it is added |
|---|---|---|
| Recirculation pump | $470 – $575 | Hot water reaches distant taps faster |
| Scale filter | $200 – $250 | Protects the heat exchanger in hard-water areas |
| Service valve kit | $120 – $150 | Isolation valves that make flushing quick |
| Permit allowance | $140 – $170 | Many areas require a permit and inspection |
| Disposal of the old heater | $45 – $55 | Included with replacements and conversions |
| Service call | $90 – $110 | Charged once per job |
Tankless or tank?
Tankless (2 bathrooms, gas)
Continuous hot water, limited by flow rate. Wall-mounted and compact. Standard like-for-like replacement: $3,000 – $3,550.
Tank (50 gallon, gas)
Hot water limited by tank size. Needs floor space for the tank. Standard like-for-like replacement: $1,700 – $2,000.
| Tankless (2 bathrooms, gas) | Tank (50 gallon, gas) | |
|---|---|---|
| Like-for-like replacement, standard | $3,000 – $3,550 | $1,700 – $2,000 |
| Hot water supply | Continuous, limited by flow rate | Limited by tank size |
| Space needed | Wall-mounted, compact | Floor space for the tank |
| Upkeep | Periodic flushing to remove scale | Periodic draining of sediment |
| Switching to it from the other type | Conversion work adds cost | Simpler |
The tank figure comes from the Tank Water Heater Cost Calculator — Link still needed. For a comparison across heater types, see the Water Heater Replacement Cost Calculator.
Regional pricing differences
Labor rates, permit fees and code requirements differ from one market to another. The calculator does not adjust for location. Treat the result as a national planning range, then get quotes from local plumbers to see where your market sits.
How to avoid unexpected costs
Ask the plumber to check the gas line size and gas meter capacity before quoting. For an electric heater, ask an electrician whether your panel has the capacity. Ask where the vent will run and whether any walls or the roof need to be opened. Ask whether a service valve kit and a condensate drain are included. Ask about utility rebates and tax credits for high-efficiency heaters before you choose a model.
Questions to ask a plumber
Which brand, model, flow rate and warranty are you quoting? Is my gas line and meter, or my electrical panel, adequate for this heater? Does the price include venting, the permit and disposal of the old heater? How often will the heater need flushing with my water? What warranty do you give on your labor?
When to hire a professional
Installing a tankless water heater involves gas or high-amperage electrical connections, correct venting of combustion gases and precise sizing of the gas supply. Mistakes can cause gas leaks, carbon monoxide hazards or a heater that cannot keep up. Many manufacturers require professional installation for the warranty, and many areas require a permit. This is a job for a licensed plumber.
Quick answers
What is the average cost to install a tankless water heater?
A gas tankless water heater for a two-bathroom home typically budgets at about $3,000 to $3,550 installed when replacing an existing tankless heater, and about $4,200 to $5,000 when converting from a tank, based on OmniEstimate’s standard planning assumptions.
What is a tankless water heater?
A tankless water heater, also called an on-demand water heater, heats water as it flows through the unit instead of storing it in a tank. It does not run out of hot water, but its output is limited by how many gallons per minute it can heat at once.
Why does converting to tankless cost more?
Converting from a tank to a tankless heater costs more because the new heater mounts on a wall, needs different venting and different connections, and often needs a larger gas line or new electrical circuits. OmniEstimate budgets about $1,150 to $1,450 for the conversion work alone.
What is a condensing tankless water heater?
A condensing tankless water heater has a second heat exchanger that captures heat from the exhaust gases. It uses less gas than a non-condensing model and can vent through plastic pipe, but it costs more to buy and needs a drain for the condensate it produces.
Frequently asked questions
How much does a tankless water heater cost installed?
A natural gas tankless water heater sized for a two-bathroom home typically budgets at about $3,000 to $3,550 installed, based on this calculator’s standard assumptions for a like-for-like replacement. A budget installation starts near $1,850 and a premium one can reach about $5,750. Converting from a tank, larger sizes and gas line upgrades cost more.
How much does it cost to switch from a tank to a tankless water heater?
Converting from a tank to a two-bathroom gas tankless heater budgets at about $4,200 to $5,000 at standard pricing. That includes a conversion allowance of about $1,150 to $1,450 for venting, wall mounting and connection changes. If the gas line is too small, a larger line adds about $390 to $480 for a short run.
Is a gas or electric tankless water heater cheaper?
An electric tankless heater is cheaper to install: about $2,600 to $3,100 for a two-bathroom size at standard pricing, against $3,000 to $3,550 for natural gas. However, whole-house electric models need several high-amperage circuits and sometimes an electrical panel upgrade, and they deliver less hot water in cold climates.
What size tankless water heater do I need?
Tankless heaters are sized by how much hot water is used at the same time, not by the number of people. The number of bathrooms is a practical guide. Homes in cold climates need more output because the incoming water is colder, so if you are between sizes, choose the larger one.
Do I need a bigger gas line for a tankless water heater?
Often, yes. A gas tankless heater burns far more gas at once than a tank water heater, so the line that fed a tank can be too small. A plumber checks this before quoting. In this calculator, a larger gas line adds about $390 to $480 for a run of up to 15 feet at standard pricing.
Do tankless water heaters need maintenance?
Yes. Minerals in the water build up as scale inside the heat exchanger, so tankless heaters need flushing from time to time, and more often in hard-water areas. A service valve kit, which adds about $120 to $150, makes flushing quick. A scale filter or water softener reduces the build-up.
Water Heater Repair Cost Calculator — Link still needed.
Is a tankless water heater worth it?
It depends on what you value. A tankless heater costs more to install than a tank: about $3,000 to $3,550 against about $1,700 to $2,000 for a 50 gallon gas tank at standard pricing. In return it does not run out of hot water, saves floor space, and avoids keeping a tank of water hot all day. Whether the energy savings repay the extra cost depends on your usage and local energy prices.
Does my ZIP code change the estimate?
No. The calculator uses your ZIP code to identify your market and match you with local professionals. It does not adjust the price. Local labor rates and permit fees do vary, so use the result as a planning range and compare it with quotes from plumbers in your area.
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