A tankless water heater cost can look affordable when you only look at the product price. Some tankless water heaters cost a few hundred dollars, while larger whole-home models can cost well over $1,000.
The installed price is different, and this is where the tankless water heater cost becomes more than the price you see on a product page.
Tankless hot water heater installation cost includes the heater, labor, removal of the old unit, fuel or electrical work, venting, permits, and any changes the home needs before the system can run properly.
In this article, we will compare cost estimates from several sources, including Angi, NerdWallet, HomeGuide, SolarReviews, and Better Homes & Gardens, then explain what those numbers mean in a real home. The goal is not to give you one fixed price. It is to help you understand the range you are likely to see and why your quote may land higher or lower.
Quick Answer: What Does Tankless Installation Usually Cost?
For a typical installed project, a realistic planning range is usually somewhere in the low thousands. Angi estimates tankless water heater installation at $1,405 to $3,899, depending on unit size and setup. That same estimate notes that permits, electrical service upgrades, and old heater removal can add $200 to $500 to the project.
NerdWallet gives a very similar range, placing tankless water heater costs at about $1,400 to $3,900, including installation. SolarReviews puts the average around $2,400, with many installations falling between $1,600 and $3,800.
Those numbers are useful for planning tankless water heater cost, but they are not a guaranteed quote. A small electric unit serving one fixture can cost much less than a full-home gas tankless conversion. A project that needs gas line work, electrical upgrades, venting changes, or relocation can cost more.
The average cost of tankless water heater installation gives you a starting point. The final price depends on the home.
Unit Price vs Installed Cost
The price of tankless water heater equipment is only one part of the bill.
HomeGuide estimates tankless units alone at about $600 to $2,600, while installed tankless systems range from about $1,400 to $5,600, depending on size, brand, and fuel type. That gap is where labor and home-preparation work show up.
A product example makes this clearer. A large electric tankless model may have a product price that looks manageable compared with a full installed quote. But larger electric units can require dedicated breakers, correctly sized wiring, and enough electrical panel capacity. The unit price does not pay for that work.
This is why the tankless water heater cost should always be viewed in two layers:
| Cost layer | What it means |
| Heater price | The appliance itself |
| Installed cost | Heater, labor, removal, permits, fuel or electrical work, venting, and setup changes |
A homeowner may see a tankless unit online and assume the project will be close to that price. In reality, the installed cost can be much higher because the home must be prepared for the new system.
Electric Tankless Water Heater Cost
The cost of installing an electric tankless water heater is often lower than a gas one when the electrical setup is already suitable. There is no gas venting, no combustion air planning, and no gas line sizing.
HomeGuide estimates an electric on-demand water heater at about $1,400 to $3,000 installed. That makes electric one look simpler at first, especially for small point-of-use units or homes that already have enough electrical capacity.
The cost changes when the home needs electrical work. A larger whole-home electric tankless unit may require dedicated circuits, new breakers, heavier wiring, open breaker space, or panel upgrades. That work can move the final price well above the product price.
An electric tankless can be a good fit when the home is ready for it. The estimate should still confirm the panel, wiring path, circuit requirements, permits, and plumbing changes.
Gas Tankless Water Heater Installation Cost
Gas tankless water heater installation cost is often shaped by fuel and venting work.
HomeGuide estimates tankless gas water heaters at about $2,100 to $5,600 for the unit, labor, and required modifications. That higher range reflects the extra work gas units can require, such as gas line sizing, venting, combustion air, and condensate drainage for condensing models.
Gas units may cost more to install, but they can also handle higher hot-water demand in many whole-home setups. That is why cost should not be judged only by the lowest upfront number. A gas unit may be more expensive to install and still make sense for a home with multiple bathrooms or higher simultaneous hot-water use.
The gas tankless water heater installation cost depends heavily on what the home already has. If the existing gas line and venting setup are suitable, the job may be more direct. If the installer needs to resize the gas line, add new venting, change the location, or add condensate drainage, the price rises.
Replacement Cost Depends on What You Already Have
Tankless water heater replacement cost is usually lower when the new system is close to what the home already supports.
Replacing one tankless unit with another similar unit may be more straightforward if the fuel type, location, venting, and water connections are compatible. Replacing a storage tank with a tankless unit can involve more changes because the home may need wall mounting, new venting, electrical work, gas line changes, or old tank removal.
Better Homes & Gardens gives a broad $1,200 to $3,500 range for tankless hot water heater replacement and notes that costs vary by type, fuel source, labor, permits, venting, and location challenges.
Here is the practical difference:
| Replacement situation | Why the cost changes |
| Tank to tankless | Often needs new mounting, venting, fuel, or electrical work |
| Tankless to tankless | May be simpler if the setup matches |
| Electric tank to electric tankless | Electrical requirements still need review |
| Gas tank to gas tankless | Venting and gas line may need changes |
| Gas to electric or electric to gas | Usually more involved because the fuel or power system changes |
The cheapest replacement is usually the one that requires the least conversion work. The more the home has to change, the more the quote can rise.
What Can Raise the Final Cost?
The final tankless water heater installation cost rises when the installer has to do more than mount the unit and connect water lines.
Common cost drivers include moving the unit to a new location, adding new venting, upgrading electrical wiring, resizing a gas line, adding condensate drainage, removing the old tank, pulling permits, adding service valves, or correcting poor access.
Some parts of the tankless water heater cost are easy to overlook. Old heater removal may look small, but it still takes labor. Permits may vary by location. A condensing gas model may need a drain. A whole-home electric model may need electrical work before it can operate. A gas model may need venting that the old tank heater did not require.
Recirculation can also add cost if the homeowner wants faster hot water at distant fixtures. It can improve comfort, but it adds design and equipment considerations.
A quote that looks low may simply be missing some of these items. That does not mean the installer is wrong, but it does mean the scope should be clarified.
Simple Cost Examples
A small electric point-of-use unit serving one sink can be one of the lower-cost tankless projects. The unit is smaller, the water demand is limited, and the installation may be simple if plumbing and electrical access are already suitable.
A whole-home electric tankless system is different. The heater may need more electrical capacity, dedicated circuits, and wiring. The electric tankless water heater installation cost can stay reasonable when the home is ready, but panel or wiring work can raise the total.
A whole-home gas tankless replacement has a different cost pattern. The unit may support higher hot-water demand, but the installer may need to check gas line capacity, venting, combustion air, and condensate drainage. That is why gas tankless water heater installation cost can be higher than a basic electric point-of-use project.
These examples are not fixed prices. They show why two tankless installations can land in very different ranges even when both involve “installing a tankless water heater.”
How to Budget Before Calling an Installer
A useful tankless water heater cost budget starts with your current setup.
Know what type of water heater you have now, where it is located, what fuel it uses, and whether you want the new tankless system in the same place. Also, think about whether you want a whole-home system or a smaller dedicated unit.
When asking for a quote, the most important question is what the price includes.
A good estimate should explain the heater price, labor, removal of the old unit, plumbing changes, electrical or gas work, venting, permits, service valves, startup testing, and cleanup. If any of those are excluded, you should know that before comparing prices.
This matters because the tankless water heater replacement cost can look very different depending on what is included in the first number.
A complete quote is easier to compare than a cheap quote with missing details.
What a Good Quote Should Separate
A clear quote should not hide everything under one vague installation price.
It should separate the appliance from the work around the appliance.
| Quote item | Why it matters |
| Unit price | Shows the cost of the heater itself |
| Labor | Shows the installation work |
| Electrical or gas work | Shows home-preparation needs |
| Venting or drainage | Important for gas and condensing units |
| Old unit removal | Affects replacement cost |
| Permits | May be required locally |
| Service valves | Help with future flushing and maintenance |
| Startup testing | Confirms the system works before the job is done |
The average cost of tankless water heater installation can help you set expectations, but the quote should show what your specific home needs.
That is the number that matters.
Budget for the Whole Installed System
The tankless hot water heater installation cost is the cost of the whole installed system.
The heater price is only the beginning. Labor, fuel type, wiring, venting, old unit removal, permits, and home preparation can all affect the final bill.
For many homeowners, the tankless water heater cost will fall somewhere in the low thousands once the unit and installation are included. Electric point-of-use projects may cost less. Whole-home gas or major conversion projects may cost more.
The most useful estimate is not simply the cheapest number. It is the one that clearly shows what the home needs, what the installer will do, and what the final system should deliver.
Sources:
- Angi: https://www.angi.com/articles/how-much-does-tankless-water-heater-cost.htm
- NerdWallet: https://www.nerdwallet.com/home-ownership/home-improvement/learn/water-heater-cost
- SolarReviews: https://www.solarreviews.com/blog/how-much-does-a-tankless-water-heater-cost
- HomeGuide: https://homeguide.com/costs/tankless-water-heater-installation-cost
- HomeGuide: https://homeguide.com/costs/water-heater-installation-cost
- Better Homes & Gardens: https://www.bhg.com/hot-water-heater-replacement-cost-8599147