Water heaters · tankless gas
Tankless gas water heater cost
A gas instantaneous (tankless) water heater at UEF 0.87 has a certified national retrofit benchmark of $1,773.49 (2023 USD) low, $2,129.14 (2023 USD) typical, and $2,646.99 (2023 USD) high.
Source year. Based on the NREL REMDB Gas Inst class in 2023 dollars.
Geographic scope. United States national modelled benchmark.
Model scope. Gas tankless / instantaneous units. The workbook regression uses UEF only (0.81–0.99). There is no certified gallon input.
Important limitation. Not a storage-tank price, not electric tankless, and not a current plumber quote.
Certified benchmark values
| Band | Value |
|---|---|
| installed low | $1,773.49 (2023 USD) |
| installed typical | $2,129.14 (2023 USD) |
| installed high | $2,646.99 (2023 USD) |
Benchmark estimator
Results are modelled 2023 USD benchmarks, not a contractor quote.
Modelled benchmark: Low $1,773.49 (2023 USD); typical $2,129.14 (2023 USD); high $2,646.99 (2023 USD)
Typical result $2,129.14 (2023 USD)
What this estimate includes
- UEF regression
- Gas Inst retrofit adder
What moves the number
- Uniform Energy Factor
- Fuel and venting, which the equation does not itemize separately
Methodology and sources
- Independent REMDB Gas Inst row.
- Entering a tank size is not supported because the published equation has no volume term.
Primary source: National Residential Efficiency Measures Database 2024.
Limitations
- 2023$ historical REMDB retrofit benchmark, not a 2026 contractor quote.
- REMDB may include upstream RSMeans/retail-derived inputs; cite REMDB only.
- Gas instantaneous / tankless UEF-only regression. Not a storage-tank total.
Questions this evidence can answer
Can I enter gallons?
No. The certified tankless equation is UEF-only. Gallon inputs would be decorative, so they are not offered.