Gas tankless water heater replacement cost in Nashville, TN
Installed, About 180,000–199,000 BTU (2–3+ bathrooms)
A typical tankless water heater (About 180,000–199,000 BTU (2–3+ bathrooms)) costs about $2,750 installed in the Nashville area, 2% below the national figure, because plumbers here earn a median $29 an hour against $31 nationally.
Prices by size in Nashville
| Size | Low | Typical | High | National typical |
|---|---|---|---|---|
| About 150,000 BTU (1–2 bathrooms) | $2,050 | $2,600 | $3,350 | $2,650 |
| About 180,000–199,000 BTU (2–3+ bathrooms) | $2,550 | $2,750 | $3,700 | $2,800 |
Local labor: what plumbers earn here
| Hourly wage | Nashville metro | United States |
|---|---|---|
| 25th percentile | $24 | $24 |
| Median | $29 | $31 |
| 75th percentile | $36 | $41 |
The Nashville market
Metro Nashville's Department of Codes and Building Safety prices a hot water heater under both plumbing permits ($43) and gas/mechanical permits ($21), with a $75 minimum per permit. Furnaces, AC units and package units are gas/mechanical appliances, with each residential appliance beyond the first at $11 and a charge of $32 per 100,000 Btuh. Reinspections cost $50. Licensed contractors apply online; anyone else applies in person, and the owner-occupant self-permit affidavit covers building work only, with separate plumbing and gas/mechanical permits still required. Electricity dominates in Tennessee: EIA's 2020 survey found 60% of homes heat with electricity and 35% with a central heat pump, 86% have central air, and 74% heat water electrically. TVA's EnergyRight program offers equipment rebates through its Quality Contractor Network.
Only about a quarter of Tennessee homes heat water with gas, so a gas tankless unit is mainly an option for Nashville homes that already have gas service. Electric tankless units need large dedicated circuits, which often means panel work by a licensed electrician. Get the vent, gas or electrical items into the quote before comparing. Ask whether isolation valves are included so the unit can be descaled.
Permits in Nashville
| Permit for this job | Yes (inferred: Metro fee schedule prices a 'Hot water heater' under both plumbing and gas/mechanical permits; no page found that states the requirement in words) (source) |
|---|---|
| Fee | Plumbing: minimum $75 per permit; hot water heater $43. Gas/mechanical: minimum $75 per permit; hot water heater $21; each residential appliance beyond the first $11; HVAC also charged 'at the rate of thirty-two dollars ($32.00) per one hundred thousand Btuh or fraction thereof'; reinspection $50. |
| Who can pull it | Unclear for homeowners; licensed contractors apply online, others apply in person |
| Inspection | Yes (reinspection fees and inspection requests apply to plumbing and gas/mechanical permits) |
Rebates in Tennessee
HEAR: announced, not open yet. HOMES: announced, not open yet. Source: TDEC Office of Energy Programs, checked October 13, 2026.
- TVA EnergyRight rebates: Heat pump $500-$800, central AC $200-$400, HPWH $900 via Quality Contractor Network
What these programs cover, and other states
Other systems in Nashville
- Gas tank water heater
- Gas furnace
- Central air conditioner
- Heat pump (ducted, outdoor unit + air handler)
Gas tankless water heater cost in other metros
Sources
- Nashville, TN permit source (water heater permit)
- Nashville, TN permit source (who can pull)
- Nashville, TN permit source (notable local rule)
- Nashville, TN permit source: Lists Metro Mechanical, Gas and Appliance and Plumbing exam
- TVA EnergyRight: residential rebates
- Tennessee Dept. of Environment and Conservation: IRA home energy rebates
- EIA RECS 2020: Highlights for space heating fuel in U.S. homes by state
- EIA RECS 2020: Highlights for space heating in U.S. homes by state
- EIA RECS 2020: Highlights for air conditioning in U.S. homes by state
- EIA RECS 2020: Highlights for water heating in U.S. homes by state
- BLS OEWS May 2025, Nashville-Davidson--Murfreesboro--Franklin, TN (47-2152 plumbers)
- DOE Gas-fired Instantaneous Water Heaters Final Rule TSD (Dec 2024), Table 8.2.6 (2023$)