FixHomeCost

Tankless Water Heater Cost

A tankless water heater usually costs about $1,500 to $5,000 installed. Electric units are cheaper to buy and install but may need an electrical panel upgrade. Gas units cost more because they often need new venting and a larger gas line. Switching from a tank adds more labor than replacing an existing tankless unit.

Typical pro cost

$1,500 to $5,000

LowHigh
Urgency
Plan ahead
DIY difficulty
Hard
Time to fix
Half a day to 1 day (pro)
Prices
US typical range

Last reviewed September 2026

Signs it's this problem

Common causes

Fuel type

Gas units need venting and often a bigger gas line; electric units need large dedicated circuits.

Unit size

Flow rate in gallons per minute sets the price. Whole-house units for several showers cost more.

Conversion from a tank

Moving from tank to tankless adds venting, gas, electrical and mounting work.

Location

Outdoor units save on venting but need freeze protection in cold climates.

Permits and code

Local permits, gas pressure tests and venting rules add cost.

How to fix it, step by step

  1. 1

    Count how many fixtures you run at once and pick a unit sized for that flow rate.

  2. 2

    Check your fuel: gas line size for gas units, or panel capacity for electric units.

  3. 3

    Get 2 to 3 quotes that list the unit model, venting, gas or electrical upgrades, permit and haul-away.

  4. 4

    Ask about a water softener or scale filter if you have hard water; scale is the main cause of tankless problems.

  5. 5

    Plan for yearly descaling to protect the warranty.

  6. 6

    Compare the total installed price with a new high-efficiency tank before deciding.

Safety: Gas piping and venting must be installed by a licensed pro. Poor venting can cause carbon monoxide problems.

Tools and materials

  • None for homeowners: installation is a pro job

Approximate DIY cost: Not a DIY job

Call a pro when

  • Any gas tankless installation
  • Converting from a tank heater
  • Upgrading the electrical panel or gas line

Tankless Water Heater Cost cost

Typical US price ranges for professional work, including labor and materials
JobTypical cost
Electric tankless water heater, installed$1,500–$3,500
Gas tankless water heater, installed$2,500–$5,000
Gas line upgrade$300–$1,000
Electrical panel upgrade for electric tankless$1,500–$4,000
Yearly descaling service$100–$250

Ranges are typical US prices compiled by FixHomeCost. Prices vary by region, home and contractor, so compare 2–3 local quotes.

Common questions

Is a tankless water heater worth it?

It can be if you use a lot of hot water, want endless hot water or plan to stay in the home 10 or more years. Energy savings alone may take many years to cover the higher upfront cost.

How long does a tankless water heater last?

About 15 to 20 years with regular descaling, longer than most tank heaters.

Can a tankless water heater run out of hot water?

It will not run out, but it can only heat a certain flow at once. Running several showers and appliances together can exceed its capacity.

Do tankless water heaters need maintenance?

Yes. Flush or descale them about once a year, and clean the inlet filter, especially with hard water.

This is general information, not a professional inspection. See how we research costs.