Quick answer: Replacing a standard tank water heater costs about $1,200–$2,500 installed (unit $400–$900 + labor $600–$1,500). Tankless runs $2,500–$5,000+ installed. The unit itself is cheaper than the install — most of the cost is labor, permits, and code upgrades. This is one job where a licensed plumber is usually worth it (gas/water/venting), but knowing the numbers keeps you from overpaying.
Before you price it out, size the unit first — the right capacity is what drives the cost.
Cost by Type
| Type | Unit | Installed (total) |
|---|---|---|
| Tank (gas/electric, 40–50 gal) | $400–$900 | $1,200–$2,500 |
| Tankless (gas) | $1,000–$2,000 | $2,500–$5,000+ |
| Heat-pump (hybrid) | $1,500–$2,500 | $2,500–$4,500 |
What Drives the Price
Labor and local rates, whether gas/venting or electrical needs upgrading to meet code, permit fees, and removal of the old unit. Switching from tank to tankless costs more because of gas-line and venting changes.
Tank vs Tankless: Is Tankless Worth It?
Tankless lasts longer (~20 years vs ~10–12), saves space, and gives endless hot water, but costs more upfront. For a straight replacement on a budget, a quality tank is the value pick. For a long-term home, tankless can pay back over time.
Should You DIY It?
Usually no — water heaters involve gas, venting, or 240V wiring and a permit in most areas. This is the kind of job our water guide flags for a pro. Where you save is buying smart and getting 2–3 quotes.
FAQ
How long does a water heater last?
A tank heater lasts about 10–12 years; tankless can last 20+. If yours is over 10 years and leaking from the tank, replace it.
Not sure the tank is the culprit yet? Diagnose the real source first in water heater leaking from the bottom.
Is it cheaper to repair or replace a water heater?
If it’s under ~8 years and the issue is a part (element, thermostat, valve), repair. If it’s old or leaking from the tank itself, replace.
Can I install a water heater myself?
Most homeowners shouldn’t — it involves gas, venting, or 240V wiring and usually a permit. Hire a licensed plumber for safety and code compliance.
🔧 Plumber-Recommended Parts & Tools
Tackling this yourself? See a licensed plumber’s picks for the best tank water heaters and top tankless units — the parts that get the job done right the first time.
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