How much does water heater replacement cost?
A standard tank water heater replacement usually costs $1,200 - $3,500 installed. Tankless replacements and conversions are commonly $3,000 - $6,500+ because gas, venting, electrical, condensate, and water-quality requirements can change the scope.
The cheapest quote is not always the best quote. Water heater replacement often needs permit handling, disposal of the old tank, expansion tank or valve work, venting checks, and a written labor warranty.
What changes the replacement price
Same-size tank swap
$1,200 - $2,500How to tell40-50 gallon tank, same fuel type, easy garage or basement access
The fixRemove old tank, install new unit, connect water/gas/electric, test, haul away
Larger tank or fuel-type complexity
$2,000 - $4,500+How to tellLarger household, 75+ gallon tank, gas venting, tight utility closet, attic, or crawlspace
The fixLarger unit, added labor, venting or platform adjustments, more difficult removal
Code and safety upgrades
$150 - $1,000+ extraHow to tellNo expansion tank where required, old shutoff valves, missing pan/drain, outdated venting
The fixBring the installation up to current local code and manufacturer requirements
Tankless replacement
$2,500 - $5,500+How to tellExisting tankless unit failed, same location and fuel type
The fixReplace unit, flush lines, reconnect venting/condensate, test flow and temperature rise
Tank-to-tankless conversion
$3,500 - $8,000+How to tellCurrent home has a tank but homeowner wants endless hot water or space savings
The fixNew tankless unit plus possible gas-line, venting, electrical, condensate, and water treatment work
Before you approve the replacement quote
- Check the age on the manufacturer label. A leaking tank or a 10-15 year old unit with major failure usually points to replacement; a newer unit may still be worth repairing.
- Ask whether the quote includes permit, disposal, pan, drain line, expansion tank, shutoff valves, venting corrections, and warranty registration.
- Ask for the exact model number, capacity, fuel type, energy rating, and labor warranty in writing.
- If you are considering tankless, ask whether gas-line sizing, venting, condensate drain, descaling, and hard-water protection are included.
Unlock the hiring checklist
Use this before you call a plumbing, so you know what to ask and what to avoid.
Call a pro when…
- The tank is leaking from the body or bottom
- The unit is old and has a major burner, gas valve, control, or element failure
- Rusty hot water, rumbling, or repeated no-hot-water symptoms keep returning
- The current install lacks required safety items or venting is questionable
- You want to change fuel type, capacity, or convert to tankless
Repair or replace?
Repair usually makes sense for a newer water heater with a failed thermostat, element, valve, thermocouple, igniter, or small fitting leak. Replacement usually makes sense for a leaking tank, repeated failures, severe corrosion, undersized capacity, or an older unit where the repair would eat a large share of replacement cost. Ask for a repair quote and replacement quote side by side when the unit is borderline.
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Related questions
How long does water heater replacement take?
A straightforward tank swap often takes 2 - 6 hours. Tankless installs, attic/crawlspace work, fuel changes, and code upgrades can take longer.
Do I need a permit to replace a water heater?
Many cities require one, especially for gas water heaters. A legitimate installer should know local requirements and tell you whether the permit is included.
Is tankless worth the extra cost?
Tankless can make sense for high hot-water demand, space savings, long service life, or homes already set up for it. It is less attractive if gas, venting, electrical, or water-treatment upgrades make the conversion expensive.
Who should install a water heater?
Use a licensed plumber or qualified water-heater installer. Gas, venting, electrical, combustion air, and pressure relief details are safety issues, not just plumbing connections.