Tankless vs tank water heater cost (2026)
A 50-gallon gas tank water heater runs about $2,400 installed in 2026. A comparable gas tankless unit runs about $5,800 installed once gas line and venting upgrades are included. Tankless lasts roughly 2x as long (15 to 20 years vs 8 to 12).
Tank, natural gas
- ✓Cheapest install by a wide margin
- ✓Any plumber can swap a 40 to 75 gallon tank in 2 to 4 hours
- ✓Works fine during a power outage on a standing pilot model
- –8 to 12 year lifespan, often less with hard water
- –Standby heat loss adds about $40 to $80 per year
- –Eats 16 sq ft of floor space
Tankless, natural gas
- ✓15 to 20 year lifespan
- ✓Endless hot water at design GPM (typically 5 to 7 GPM)
- ✓Wall-mounts, frees a closet or garage corner
- –Install often needs a larger gas line and stainless venting
- –Cold-water sandwich at short draws is a real annoyance
- –Annual descale service in hard-water markets
Side by side
| Tank | Tankless | |
|---|---|---|
| Typical installed cost | $2,400 | $5,750 |
| Typical lifespan | 8 to 12 years | 15 to 20 years |
| Standby loss | About 50 to 80 W continuous | Near zero |
| Hot water cap | Tank capacity then recovery | Endless at rated GPM |
| Federal credit eligible | Some condensing tanks | Most condensing tankless |
Pick Tank if
You're doing a like-for-like swap, the existing tank lasted, and the budget gap matters more than 10 years of lifespan.
Pick Tankless if
You have natural gas, hot water demand at 3+ fixtures, and plan to stay in the home at least 8 years.
Still deciding? Get quotes for both
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Request comparison quotesFrequently asked questions
Will tankless really pay for itself?+
On energy savings alone, payback runs 12 to 18 years for gas tankless versus gas tank. The honest reason to switch is lifespan, space, and not running out of hot water mid-shower, not the energy bill.
Can I install tankless without upgrading the gas line?+
Almost never. A whole-home gas tankless needs 150,000 to 199,000 BTU input, which usually requires 3/4 inch or larger pipe from the meter. Plan for $600 to $1,500 in gas work on top of the unit and labor.
Is electric tankless a real option?+
For a whole house in a cold-climate state, no. The amperage draw is brutal and the panel often can't support it. Electric tankless makes sense as point-of-use at a remote bathroom or kitchen sink.