Tankless Water Heater Installation Cost in Washington
$1,500 – $4,750We estimate tankless water heater installation in Washington at $1,500 to $4,750 for a whole-house tankless unit replacing a tank. The national estimate is $1,400 to $4,400. Washington plumber pay is 27% above the national median, ranking 8 of 51.
| Part of the job | Low | High |
|---|---|---|
| Parts and materials (our assumption) | $1,000 | $3,000 |
| Labor hours (our assumption) | 5 | 10 |
| Billed labor rate per hour | $97 | $175 |
| Estimated total | $1,500 | $4,750 |
Our estimate, not a quote. Billed rate is the Washington median wage from BLS (2025, $38.96 an hour) times 2.5 to 4.5 to cover payroll costs, overhead, travel and profit. How we estimate
What our assumptions are based on
| Item | Sourced figure | Basis | Source |
|---|---|---|---|
| Labor hours | 4 – 10 | 4 to 8 hours (This Old House); 6 to 10 hours (Fixr). Bob Vila says close to 3 hours; that figure is not in this range. | This Old House, Fixr |
What other publishers report
| Publisher | Low | High | Scope |
|---|---|---|---|
| This Old House | $1,200 | $3,500 | Equipment and labor. Page dated June 2026. |
| Fixr | $2,500 | $4,500 | National average range, installed. Page dated January 2025. |
| Bob Vila | $1,333 | $3,721 | Installed, citing Angi and HomeAdvisor. Page dated October 2023. |
Cities in Washington
| Metro area | Median wage | Low | High |
|---|---|---|---|
| Seattle | $45.78 | $1,550 | $5,050 |
Who can legally do this in Washington
All plumbing contract work must be performed by a Licensed Plumbing Contractor, and each must designate a certified plumber. General contractors may do plumbing work only if they also hold a plumbing contractor license.
Compared with neighboring states
Other plumber jobs in Washington
- Toilet Replacement
- Faucet Replacement
- Drain Cleaning
- Garbage Disposal Replacement
- Water Heater Replacement
- Pipe Repair
- Whole-House Repipe
- Sewer Line Repair
Tankless Water Heater Installation cost in every state · Washington home repair guide
Sources
General information, not professional advice. Conditions, codes and prices vary. Turn off power, gas or water before any work, and hire a licensed professional when in doubt. Cost figures are our estimates, not quotes.