Switching to a tankless water heater is one of the smartest upgrades you can make at home. You get hot water on demand, lower energy bills, and a unit that lasts nearly twice as long as a traditional tank. But before you commit, you need a clear picture of the costs involved.
So, how much to install tankless water heater? Most homeowners spend between $1,000 and $3,500 total, including the unit and labor. The final number depends on fuel type, unit size, and what upgrades your home needs to support it. This guide breaks every cost down so there are no surprises.
How Much Is a Tankless Water Heater?
The unit itself is the biggest part of the cost. Here is a general price range:
| Unit Type | Unit Cost (Equipment Only) |
| Electric (point-of-use) | $150 to $400 |
| Electric (whole-home) | $500 to $1,200 |
| Gas (standard) | $500 to $1,000 |
| Gas (high-efficiency/condensing) | $1,000 to $2,000 |
| Propane | $500 to $1,500 |
Gas units cost more upfront but heat water faster and handle higher demand. Electric units are cheaper to buy but may struggle to supply an entire home in colder climates.
Brand matters too. Rinnai, Navien, and Rheem are among the most reliable brands. Budget brands may save money at purchase but often cost more in repairs over time.
You can read about: How to Install Tankless Water Heater
Tankless Water Heater Installation Cost by Fuel Type
Fuel type is the biggest driver of total tankless water heater installation cost. It affects both the unit price and the labor needed to install it.
Gas Tankless Water Heater Installation Cost
Gas units are the most popular choice for whole-home use. They heat water quickly and handle multiple simultaneous demands with ease.
Total cost: $1,000 to $3,500
This range includes the unit, labor, new gas line work (if needed), and venting. Gas units require proper venting to the outside to remove combustion gases. If your home does not already have a dedicated gas line for the unit, adding one adds $300 to $800 to the total.
Condensing gas units cost more upfront, around $1,000 to $2,000 for the unit alone, but they are 10 to 15 percent more efficient than standard gas units. The energy savings offset the extra cost over time.
Electric Tankless Water Heater Installation Cost
Electric units are easier and cheaper to install because there is no venting required.
Total cost: $800 to $1,500
The lower labor cost makes electric units attractive. But most older homes need an electrical panel upgrade to support a whole-home electric tankless unit. That upgrade adds $500 to $2,000 depending on the panel size needed. Factor that in before assuming electric is the cheaper option.
Point-of-use electric units, which serve a single fixture like a bathroom sink, cost much less. Total installed cost is typically $300 to $700.
Propane Tankless Water Heater Installation Cost
Propane units work similarly to natural gas units and are common in rural areas where natural gas lines are not available.
Total cost: $1,500 to $3,500
Installation involves venting and propane line connections. If you do not already have a propane tank, adding one costs an additional $400 to $2,000 depending on size and whether you rent or buy.
How Much Does Tankless Water Heater Installation Cost by Unit Size?
The size of the unit is measured in gallons per minute (GPM). This tells you how much hot water it can deliver at once.
| Household Size | Recommended GPM | Estimated Total Cost |
| 1 to 2 people | 6 to 8 GPM | $800 to $1,500 |
| 3 to 4 people | 8 to 10 GPM | $1,200 to $2,500 |
| 5+ people | 10+ GPM | $2,000 to $3,500+ |
Undersizing a unit is a common and costly mistake. If the unit cannot keep up with demand, you end up with lukewarm water during peak use. A plumber can calculate the right GPM for your household based on the number of fixtures and your climate zone.
What Additional Costs Affect Tankless Water Heater Installation?
The unit and labor are just the starting point. Several additional costs can affect the total cost of tankless water heater and installation.
Permit Fees
Most cities require a permit for water heater installation. Permit fees typically run $50 to $200. A licensed plumber usually handles the permit as part of their service. Do not skip this step. An unpermitted installation can cause problems when you sell your home.
Venting and Exhaust Work
Gas units need venting to the outside. If you are replacing a tank heater that was vented differently, new vent pipes may be needed. Venting work adds $300 to $1,000 to the project.
Condensing units use PVC vent pipes, which are cheaper to install than metal flue pipes used by standard gas units.
Gas Line Upgrades
Tankless gas units need a larger gas supply than most tank heaters. If your current gas line is too small, a plumber will need to run a new line or resize the existing one. This costs $200 to $800 depending on the distance and complexity.
Electrical Panel Upgrades
Whole-home electric tankless units draw a lot of power. Many require 200-amp service and multiple dedicated circuits. If your panel cannot handle it, an upgrade costs $500 to $2,000.
Water Softener or Descaler
Hard water causes mineral buildup inside tankless units, which reduces efficiency and shortens the unit’s life. If your area has hard water, a water softener or an inline scale filter is a smart addition. Cost: $200 to $600 for a basic filter, $800 to $2,000 for a full softener system.
Removing the Old Unit
If you are replacing a traditional tank heater, there is a disposal cost. Most plumbers charge $50 to $150 to haul away the old tank.
Tankless vs. Standard Water Heaters
Understanding the full picture helps you decide which makes more sense for your home.
| Factor | Tank Water Heater | Tankless Water Heater |
| Unit cost | $300 to $900 | $500 to $2,000 |
| Installation cost | $200 to $500 | $500 to $1,500 |
| Lifespan | 8 to 12 years | 20 to 25 years |
| Energy efficiency | 60 to 70% | 80 to 95% |
| Hot water supply | Limited by tank size | Unlimited on demand |
| Annual energy savings | — | $100 to $300 vs. tank |
The tankless hot water heater cost is higher upfront. But the longer lifespan and lower monthly energy bills mean most homeowners break even within 5 to 8 years. After that, the savings are a pure benefit.
DIY vs. Professional Water Heater Installation
Some homeowners ask whether they can install a tankless unit themselves to save on labor.
The honest answer is: it depends on the type and your skill level.
Electric point-of-use units are the most DIY-friendly. If you are comfortable working with electrical wiring and the unit is small, installation is manageable for an experienced DIYer.
Whole-home gas or electric units are a different story. Gas line work requires a licensed professional in most states. Electrical panel work must meet code and be inspected. Venting must be installed correctly or carbon monoxide can enter the home.
DIY installation on a gas unit can void the manufacturer warranty and create serious safety risks. Labor costs for professional installation typically run $500 to $1,500. That is money well spent for peace of mind and proper code compliance.
How Can You Save on Tankless Water Heater Installation Costs?
There are real ways to reduce how much to install tankless water heater without cutting corners on quality.
Take advantage of federal tax credits. As of 2026, the federal Energy Efficient Home Improvement Credit allows homeowners to claim up to 30 percent of the cost of qualifying energy-efficient water heaters, up to $600. Check the manufacturer specs to confirm your unit qualifies.
Look for utility rebates. Many gas and electric utilities offer rebates for switching to tankless units. Rebates of $50 to $300 are common. Check your utility provider’s website or ask your plumber.
Get at least three quotes. Labor costs vary significantly between contractors. Getting multiple quotes helps you find fair pricing without sacrificing quality. Be cautious of quotes that are much lower than others. That can signal shortcuts or unlicensed work.
Bundle with other plumbing work. If you are already having plumbing done, adding a water heater installation at the same time reduces total labor costs. Plumbers often discount bundled jobs.
Choose a mid-range unit. The most expensive unit is not always the best choice for your household. A mid-range unit from a reliable brand like Rinnai or Rheem often delivers the best balance of performance and value.
How Does a Tankless Water Heater Work?
Understanding the basics helps you make a better buying decision and maintain the unit properly.
A tankless water heater heats water directly as it flows through the unit. When you turn on a hot tap, cold water enters the unit and passes over a heat exchanger. Either a gas burner or an electric element heats the exchanger, which warms the water instantly.
Because there is no storage tank, there is no standby heat loss. A traditional tank heater constantly reheats stored water to keep it at temperature, even when no one is using it. That standby energy use accounts for a significant portion of your water heating bill.
The trade-off is flow rate. If you run multiple hot water fixtures at the same time, a unit that is too small will struggle to keep up. That is why sizing matters so much.
Is Tankless Water Heater Installation Worth It?
For most homeowners, yes. Here is why:
Longer lifespan. A tankless unit lasts 20 to 25 years. A standard tank lasts 8 to 12. Over the long run, you buy fewer units.
Lower energy bills. The U.S. Department of Energy estimates that tankless units are 24 to 34 percent more energy-efficient than tank heaters for homes that use 41 gallons or less per day. Larger households see efficiency gains of 8 to 14 percent.
Unlimited hot water. No more cold showers because someone used all the hot water. A properly sized unit delivers hot water continuously.
Space savings. Tankless units are wall-mounted and compact. They free up the floor space a large tank takes up.
The tankless hot water heater cost is real, and the upfront investment is higher than a replacement tank. But for homeowners planning to stay in their home long-term, the savings and convenience make it worth the investment.
Conclusion
Knowing how much to install tankless water heater helps you plan a realistic budget and avoid unexpected costs. Most homeowners spend between $1,000 and $3,500 total. Fuel type, unit size, venting, and any required upgrades all affect the final number.
The best way to get an accurate estimate is to talk to a licensed plumber who can assess your home’s current setup and recommend the right unit for your needs.
If you are in the Los Angeles area, Derks Plumbing specializes in professional Tankless Water Heater Installation in Eagle Rock and surrounding neighborhoods. Their licensed team handles everything from permits and gas line upgrades to final installation and inspection, so you get the job done right the first time.
FAQs
How much does it cost to install a tankless water heater on average?
Most homeowners spend $1,000 to $3,500 total. The range depends on fuel type, unit size, and what upgrades your home needs to support the new unit.
What is the tankless water heater installation cost for gas units?
Gas tankless water heater installation typically costs $1,000 to $3,500 total, including the unit, venting, gas line work, and labor.
Is the tankless hot water heater cost worth it compared to a tank?
Yes, for most homeowners. Tankless units last twice as long and use 24 to 34 percent less energy. The upfront cost is offset by savings over time.
What is the cost of a tankless water heater and installation for electric units?
Electric whole-home units typically cost $800 to $1,500 installed. However, panel upgrades can add $500 to $2,000 if your electrical service cannot support the unit.
Do I need a permit to install a tankless water heater?
Yes, in most cities. Permit fees run $50 to $200. A licensed plumber handles this as part of the installation process.
